GROUTING TECHNIQUES IN BOTTOM SEALING OF HAZARDOUS WASTE SITES

EPA Science Inventory

Bottom sealing of hazardous waste sites involves the injection or insertion of an inert impermeable and continuous horizontal barrier in soil below the source of contamination. This type of containment strategy could be used in conjunction with other technology such as slurry wal...

Effects of hydrologic modifications on salinity and formation of hypoxia in the Mississippi River-Gulf Outlet and adjacent waterways, southeastern Louisiana, 2008 to 2012

USGS Publications Warehouse

Swarzenski, Christopher M.; Mize, Scott V.

2014-01-01

The Mississippi River-Gulf Outlet (MRGO) was constructed between 1958 and 1968 to provide a safer and shorter route between the Gulf of Mexico and the Port of New Orleans for ocean-going vessels. In 2006, the U.S. Congress directed the U.S. Army Corps of Engineers (USACE) to develop and implement a plan to deauthorize a portion of the MRGO ship channel from its confluence with the Gulf Intracoastal Waterway to the Gulf of Mexico. In 2009, in accordance with plans submitted to Congress, the USACE built a rock barrier across the MRGO near Hopedale, Louisiana. Following Hurricane Katrina, Congress also authorized the USACE to implement the Hurricane Storm Damage Risk Reduction System (HSDRRS) by building structures in the MRGO and adjacent surface waters, to reduce vulnerability of this area to storm surge. The HSDRRS includes the Gulf Intracoastal Waterway-Lake Borgne Surge Barrier and Gate Complex near mile 58 of the deauthorized portion of the MRGO and the Seabrook Gate Complex on the Inner Harbor Navigation Canal (IHNC). By blocking or limiting tidal exchange in the MRGO, these barriers could affect water quality in the MRGO and nearby waters including Lake Pontchartrain, the IHNC, and Lake Borgne. In 2008, the U.S. Geological Survey, in cooperation with the USACE, began a study to document the effects of the construction activities on salinity and dissolved oxygen in these surface waters. Data were collected from August 2008 through October 2012. Completion of the rock barrier in the vicinity of mile 35 in July 2009 reduced hydrologic circulation and separated the MRGO into two distinct salinity regimes, with substantially fresher conditions prevailing upstream from the rock barrier. The rock barrier also contributed to a zone of hypoxia (dissolved oxygen less than 2 milligrams per liter) that formed along the channel bottom during the warmer summer months in each year of this monitoring; the zone was much more developed downstream from the rock barrier. The most extensive hypoxic zone was measured in October 2009 when it extended at least 34 miles in the MRGO, from mile 20 to mile 54. Construction of the surge barrier and flood gates did not affect salinity or dissolved oxygen in any comparable manner. The factors that contributed the most to hypoxia in the MRGO were the reductions in tidal water movement there after completion of the rock barrier combined with the channel depth in the MRGO, in places 10 to 30 feet deeper than surrounding surface water bodies. These factors helped to stratify salinity by reducing vertical mixing in the water column.

Shingle System And Method

DOEpatents

Dinwoodie, Thomas L.

2005-04-26

A barrier, such as a PV module, is secured to a base by a support to create a shingle assembly with a venting region defined between the barrier and base for temperature regulation. The bottom edges of the barriers of one row may overlap the top edges of the barriers of another row. The shingle assemblies may be mounted by first mounting the bases to an inclined surface; the barriers may be then secured to the bases using the supports to create rows of shingle assemblies defining venting regions between the barriers and the bases for temperature regulation.

Construction demolition wastes, Waelz slag and MSWI bottom ash: a comparative technical analysis as material for road construction.

PubMed

Vegas, I; Ibañez, J A; San José, J T; Urzelai, A

2008-01-01

The objective of the study is to analyze the technical suitability of using secondary materials from three waste flows (construction and demolition waste (CDW), Waelz slag and municipal solid waste incineration (MSWI) bottom ash), under the regulations and standards governing the use of materials for road construction. A detailed technical characterization of the materials was carried out according to Spanish General Technical Specifications for Road Construction (PG3). The results show that Waelz slag can be adequate for using in granular structural layers, while CDW fits better as granular material in roadbeds. Likewise, fresh MSWI bottom ash can be used as roadbed material as long as it does not contain a high concentration of soluble salts. This paper also discusses the adequacy of using certain traditional test methods for natural soils when characterizing secondary materials for use as aggregates in road construction.

The Use of Reactive Materials in Septic Systems for Pathogens and Nitrate Removal

NASA Astrophysics Data System (ADS)

Suhogusoff, A. V.; Hirata, R.; Aravena, R.; Stimson, J.; Robertson, W.

2009-05-01

The developing countries have an urgent need for cheap and efficient techniques for the improvement of sanitary conditions in areas without public water supply and sewerage system, especially in suburban regions or irregular occupation areas, where there is a great lack of social assistance. In this type of situations, the inhabitants use dug wells for water use and cesspits for disposal of sewage, which usually contaminates the groundwater with nitrate and microorganisms. As part of a study aiming to develop new sewage treatment systems in an irregular occupation area located at the District of Barragem, south region of the municipality of São Paulo (Brazil), a conventional cesspit (named as "Control") and an alternative septic system were constructed and monitored for a year. The design of the alternative septic system included a 1m thickness reactive barrier constituted by BOF (Budget Oxygen Furnace - a byproduct of the steel-making industry) for pathogens removal, then 1m sand package where the wastewater is oxidized and at the bottom the wastewater is in contact with a 0,5m thickness reactive barrier constituted by sawdust (carbon source), where redox conditions are very reducing and denitrification and even methanogenesis can take place. The chemical and biological data collected in the alternative septic system showed complete removal of the pathogens in the BOF barrier, then nitrification occurred between the BOF and the bottom of sand package. However denitrification in the sawdust barrier was incomplete because of the high pH caused by the BOF materials, which can reduced the number of denitrifiers bacteria present in the sawdust barrier. Isotope analyses that are been carried out in the residual nitrate will provided more information about the extent of the denitrification reaction in the alternative septic system. In case of the control cesspit, it was observed the occurrence of high concentration of ammonium, dissolved organic carbon, CO2, CH4 and low dissolved oxygen, which means the whole cesspit works like a septic tank, and probably nitrification will occur below the cesspit. It is possible that saturated conditions were achieved within the control cesspit, which reduced the input of oxygen in the wastewater. This study have shown for a better treatment of wastewater, the design should be a sand bed below septic tank for nitrification occurrence, followed by sawdust barrier for denitrification reaction, and then BOF barrier, whose high pH produced will be responsible for microorganisms removal.

15. SAME ROOMVIEW SOUTH TOWARDS THREE BOATS UNDER CONSTRUCTION. FLATBOTTOM ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. SAME ROOM-VIEW SOUTH TOWARDS THREE BOATS UNDER CONSTRUCTION. FLAT-BOTTOM SECTION IN FOREGROUND ON SAW HORSES (NOTE FRAME PATTERNS ON BOTTOM PLANKS), BACKGROUND BOATS BEING FRAMED AND PLANKED. - Lowell's Boat Shop, 459 Main Street, Amesbury, Essex County, MA

Review of coal bottom ash and coconut shell in the production of concrete

NASA Astrophysics Data System (ADS)

Faisal, S. K.; Mazenan, P. N.; Shahidan, S.; Irwan, J. M.

2018-04-01

Concrete is the main construction material in the worldwide construction industry. High demand of sand in the concrete production have been increased which become the problems in industry. Natural sand is the most common material used in the construction industry as natural fine aggregate and it caused the availability of good quality of natural sand keep decreasing. The need for a sustainable and green construction building material is required in the construction industry. Hence, this paper presents utilization of coal bottom ash and coconut shell as partial sand replacement in production of concrete. It is able to save cost and energy other than protecting the environment. In summary, 30% usage of coal bottom ash and 25% replacement of coconut shell as aggregate replacement show the acceptable and satisfactory strength of concrete.

"I provide the pleasure, I control it": sexual pleasure and "bottom" identity constructs amongst gay youth in a Stepping Stones workshop.

PubMed

Kiguwa, Peace

2015-11-01

This paper explores the meanings attached to gay sexuality through the self-labelling practices of a group of young gay-identified students in focus group and individual interviews in Johannesburg, South Africa. These meanings include constructs of the dynamics surrounding safe sex negotiation and risk related to "top-bottom" subject positioning as well as the erotics of power and desire that are imbued in these practices and positioning. Using performativity theory as a theoretical tool of analysis, I argue that constructs of "top-bottom" subjectivities can be seen to meet certain erotic needs for LGBTI youth, including reasons related to physical safety for LGBTI people living in dangerous spaces. The performance of "bottom" identities in sexual intimacy and behaviour is further deployed in the expression and performance of power that the participants construct as erotic. The implications for sexual health intervention include understanding the gendered performance influences of sexual behaviour including safe sex, exploring creative ways that practices of sexual health can be engaged with this population group in a way that accommodates the erotic pleasure interfaced with sexual identity identifications and performances of "bottom" identities. Copyright © 2015 Elsevier Inc. All rights reserved.

Energy Conversion Alternatives Study (ECAS), General Electric Phase 1. Volume 3: Energy conversion subsystems and components. Part 1: Bottoming cycles and materials of construction

NASA Technical Reports Server (NTRS)

Shah, R. P.; Solomon, H. D.

1976-01-01

Energy conversion subsystems and components were evaluated in terms of advanced energy conversion systems. Results of the bottoming cycles and materials of construction studies are presented and discussed.

241-AP Tank Farm Construction Extent of Condition Review for Tank Integrity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barnes, Travis J.; Gunter, Jason R.; Reeploeg, Gretchen E.

2014-04-04

This report provides the results of an extent of condition construction history review for the 241-AP tank farm. The construction history of the 241-AP tank farm has been reviewed to identify issues similar to those experienced during tank AY-102 construction. Those issues and others impacting integrity are discussed based on information found in available construction records, using tank AY-102 as the comparison benchmark. In the 241-AP tank farm, the sixth double-shell tank farm constructed, tank bottom flatness, refractory material quality, post-weld stress relieving, and primary tank bottom weld rejection were improved.

Performance evaluation of intermediate cover soil barrier for removal of heavy metals in landfill leachate.

PubMed

Suzuki, Kazuyuki; Anegawa, Aya; Endo, Kazuto; Yamada, Masato; Ono, Yusaku; Ono, Yoshiro

2008-11-01

This pilot-scale study evaluated the use of intermediate cover soil barriers for removing heavy metals in leachate generated from test cells for co-disposed fly ash from municipal solid waste incinerators, ash melting plants, and shredder residue. Cover soil barriers were mixtures of Andisol (volcanic ash soil), waste iron powder, (grinder dust waste from iron foundries), and slag fragments. The cover soil barriers were installed in the test cells' bottom layer. Sorption/desorption is an important process in cover soil bottom barrier for removal of heavy metals in landfill leachate. Salt concentrations such as those of Na, K, and Ca in leachate were extremely high (often greater than 30 gL(-1)) because of high salt content in fly ash from ash melting plants. Concentrations of all heavy metals (nickel, manganese, copper, zinc, lead, and cadmium) in test cell leachates with a cover soil barrier were lower than those of the test cell without a cover soil barrier and were mostly below the discharge limit, probably because of dilution caused by the amount of leachate and heavy metal removal by the cover soil barrier. The cover soil barriers' heavy metal removal efficiency was calculated. About 50% of copper, nickel, and manganese were removed. About 20% of the zinc and boron were removed, but lead and cadmium were removed only slightly. Based on results of calculation of the Langelier saturation index and analyses of core samples, the reactivity of the cover soil barrier apparently decreases because of calcium carbonate precipitation on the cover soil barriers' surfaces.

Utilization of power plant bottom ash as aggregates in fiber-reinforced cellular concrete.

PubMed

Lee, H K; Kim, H K; Hwang, E A

2010-02-01

Recently, millions tons of bottom ash wastes from thermoelectric power plants have been disposed of in landfills and coastal areas, regardless of its recycling possibility in construction fields. Fiber-reinforced cellular concrete (FRCC) of low density and of high strength may be attainable through the addition of bottom ash due to its relatively high strength. This paper focuses on evaluating the feasibility of utilizing bottom ash of thermoelectric power plant wastes as aggregates in FRCC. The flow characteristics of cement mortar with bottom ash aggregates and the effect of aggregate type and size on concrete density and compressive strength were investigated. In addition, the effects of adding steel and polypropylene fibers for improving the strength of concrete were also investigated. The results from this study suggest that bottom ash can be applied as a construction material which may not only improve the compressive strength of FRCC significantly but also reduce problems related to bottom ash waste.

In-situ formation of multiphase air plasma sprayed barrier coatings for turbine components

DOEpatents

Subramanian, Ramesh

2001-01-01

A turbine component (10), such as a turbine blade, is provided which is made of a metal alloy (22) and a base, planar-grained thermal barrier layer (28) applied by air plasma spraying on the alloy surface, where a heat resistant ceramic oxide overlay material (32') covers the bottom thermal barrier coating (28), and the overlay material is the reaction product of the precursor ceramic oxide overlay material (32) and the base thermal barrier coating material (28).

Test matrices for evaluating cable median barriers placed in v-ditches.

DOT National Transportation Integrated Search

2012-07-01

Cable barrier systems designed to be used in median ditches have been traditionally full-scale crash tested placed either : within 4 ft from the slope break point (SBP) of a 4H:1V front slope or near the bottom of the ditch. Recently, there has been ...

Barriers of lean construction implementation in the Moroccan construction industry

NASA Astrophysics Data System (ADS)

Bajjou, Mohamed Saad; Chafi, Anas

2018-04-01

Improving the production system performance has become a fundamental pillar that must be taken into consideration in the construction industry. Recent developments in the construction sector have led to renewed interest in new techniques of management. Lean Construction is a very effective approach that has gained a high popularity by its ability to eliminate waste and maximize the value for the customer. Although both developed and developing countries have gained large benefits by implementing Lean Construction approach, several experiences showed many barriers that are hindering its implementation especially in developing countries. This paper aims to assess the critical barriers to the successful implementation in the Moroccan construction industry. Based on a literature review, followed by an analysis of data collected from a questionnaire survey which targeted 330 practitioners in the Moroccan construction field, several barriers were identified as key barriers. The findings of this investigation revealed that there are significant barriers such as Lack of knowledge about Lean Construction concepts, Unskilled Human Resources, and insufficient financial resources.

Computer-aided design of nano-filter construction using DNA self-assembly

NASA Astrophysics Data System (ADS)

Mohammadzadegan, Reza; Mohabatkar, Hassan

2007-01-01

Computer-aided design plays a fundamental role in both top-down and bottom-up nano-system fabrication. This paper presents a bottom-up nano-filter patterning process based on DNA self-assembly. In this study we designed a new method to construct fully designed nano-filters with the pores between 5 nm and 9 nm in diameter. Our calculations illustrated that by constructing such a nano-filter we would be able to separate many molecules.

Water-quality data from shallow pond-bottom groundwater in the Fishermans Cove area of Ashumet Pond, Cape Cod, Massachusetts, 2001–2010

USGS Publications Warehouse

McCobb, Timothy D.; LeBlanc, Denis R.

2011-01-01

The U.S. Geological Survey (USGS) collected water-quality data between 2001 and 2010 in the Fishermans Cove area of Ashumet Pond, Falmouth, Massachusetts, where the eastern portion of a treated-wastewater plume, created by more than 60 years of overland disposal, discharges to the pond. Temporary drive points were installed, and shallow pond-bottom groundwater was sampled, at 167 locations in 2001, 150 locations in 2003, and 120 locations in 2004 to delineate the distribution of wastewater-related constituents. In 2004, the Air Force Center for Engineering and the Environment (AFCEE) installed a pond-bottom permeable reactive barrier (PRB) to intercept phosphate in the plume at its discharge point to the pond. The USGS monitored the performance of the PRB by collecting samples from temporary drive points at multiple depth intervals in 2006 (200 samples at 76 locations) and 2009 (150 samples at 90 locations). During the first 5 years after installation of the PRB, water samples were collected periodically from five types of pore-water samplers that had been permanently installed in and near the PRB during the barrier's emplacement. The distribution of wastewater-related constituents in the pond-bottom groundwater and changes in the geochemistry of the pond-bottom groundwater after installation of the PRB have been documented in several published reports that are listed in the references.

Tentative to use wastes from thermal power plants for construction building materials

NASA Astrophysics Data System (ADS)

Bui, Quoc-Bao; Phan, To-Anh-Vu; Tran, Minh-Tung; Le, Duc-Hien

2018-04-01

Thermal power plants (TPP) generates wastes (bottom and fly ashes) which become a serious environmental problem in Vietnam. Indeed, although in several countries fly ash can be used for cement industry, fly ash from actual TPP in Vietnam does not have enough good quality for cement production, because the fly ash treatment phase has not yet included in the generations of existing Vietnamese TPP. That is why bottom ash and fly ash purely become wastes and their evacuation is an urgent demand of the society. This paper presents an investigation using fly and bottom ashes in the manufacturing of construction materials. The main aims of this study is to reduce environmental impacts of fly and bottom ashes, and to test another non-conventional binder to replace cement in the manufacture of unburnt bricks. Several proportions of fly ash, bottom ash, cement, gravel, sand and water were tested to manufacture concretes. Then, geopolymer was prepared from the fly ash and an activator. Specimens were tested in uniaxial compressions. Results showed that the cement concrete tested had the compressive strengths which could be used for low rise constructions and the material using geopolymer could be used for non-load-bearing materials (unburnt bricks).

Life cycle assessment of disposal of residues from municipal solid waste incineration: recycling of bottom ash in road construction or landfilling in Denmark evaluated in the ROAD-RES model.

PubMed

Birgisdóttir, H; Bhander, G; Hauschild, M Z; Christensen, T H

2007-01-01

Two disposal methods for MSWI bottom ash were assessed in a new life cycle assessment (LCA) model for road construction and disposal of residues. The two scenarios evaluated in the model were: (i) landfilling of bottom ash in a coastal landfill in Denmark and (ii) recycling of bottom ash as subbase layer in an asphalted secondary road. The LCA included resource and energy consumption, and emissions associated with upgrading of bottom ash, transport, landfilling processes, incorporation of bottom ash in road, substitution of natural gravel as road construction material and leaching of heavy metals and salts from bottom ash in road as well as in landfill. Environmental impacts associated with emissions to air, fresh surface water, marine surface water, groundwater and soil were aggregated into 12 environmental impact categories: Global Warming, Photochemical Ozone Formation, Nutrient Enrichment, Acidification, Stratospheric Ozone Depletion, Human Toxicity via air/water/soil, Ecotoxicity in water/soil, and a new impact category, Stored Ecotoxicity to water/soil that accounts for the presence of heavy metals and very persistent organic compounds that in the long-term might leach. Leaching of heavy metals and salts from bottom ash was estimated from a series of laboratory leaching tests. For both scenarios, Ecotoxicity(water) was, when evaluated for the first 100 yr, the most important among the twelve impact categories involved in the assessment. Human Toxicity(soil) was also important, especially for the Road scenario. When the long-term leaching of heavy metals from bottom ash was evaluated, based on the total content of heavy metals in bottom ash, all impact categories became negligible compared to the potential Stored Ecotoxicity, which was two orders of magnitudes greater than Ecotoxicity(water). Copper was the constituent that gave the strongest contributions to the ecotoxicities. The most important resources consumed were clay as liner in landfill and the groundwater resource which was potentially spoiled due to leaching of salts from bottom ash in road. The difference in environmental impacts between landfilling and utilization of bottom ash in road was marginal when these alternatives were assessed in a life cycle perspective.

The Secret of the Svalbard Sea Ice Barrier

NASA Technical Reports Server (NTRS)

Nghiem, Son V.; Van Woert, Michael L.; Neumann, Gregory

2004-01-01

An elongated sea ice feature called the Svalbard sea ice barrier rapidly formed over an area in the Barents Sea to the east of Svalbard posing navigation hazards. The secret of its formation lies in the bottom bathymetry that governs the distribution of cold Arctic waters masses, which impacts sea ice growth on the water surface.

Escape driven by alpha-stable white noises.

PubMed

Dybiec, B; Gudowska-Nowak, E; Hänggi, P

2007-02-01

We explore the archetype problem of an escape dynamics occurring in a symmetric double well potential when the Brownian particle is driven by white Lévy noise in a dynamical regime where inertial effects can safely be neglected. The behavior of escaping trajectories from one well to another is investigated by pointing to the special character that underpins the noise-induced discontinuity which is caused by the generalized Brownian paths that jump beyond the barrier location without actually hitting it. This fact implies that the boundary conditions for the mean first passage time (MFPT) are no longer determined by the well-known local boundary conditions that characterize the case with normal diffusion. By numerically implementing properly the set up boundary conditions, we investigate the survival probability and the average escape time as a function of the corresponding Lévy white noise parameters. Depending on the value of the skewness beta of the Lévy noise, the escape can either become enhanced or suppressed: a negative asymmetry parameter beta typically yields a decrease for the escape rate while the rate itself depicts a non-monotonic behavior as a function of the stability index alpha that characterizes the jump length distribution of Lévy noise, exhibiting a marked discontinuity at alpha=1. We find that the typical factor of 2 that characterizes for normal diffusion the ratio between the MFPT for well-bottom-to-well-bottom and well-bottom-to-barrier-top no longer holds true. For sufficiently high barriers the survival probabilities assume an exponential behavior versus time. Distinct non-exponential deviations occur, however, for low barrier heights.

The encapsulation of cell-free transcription and translation machinery in vesicles for the construction of cellular mimics.

PubMed

Spencer, Amy C; Torre, Paola; Mansy, Sheref S

2013-10-21

As interest shifts from individual molecules to systems of molecules, an increasing number of laboratories have sought to build from the bottom up cellular mimics that better represent the complexity of cellular life. To date there are a number of paths that could be taken to build compartmentalized cellular mimics, including the exploitation of water-in-oil emulsions, microfluidic devices, and vesicles. Each of the available options has specific advantages and disadvantages. For example, water-in-oil emulsions give high encapsulation efficiency but do not mimic well the permeability barrier of living cells. The primary advantage of the methods described herein is that they are all easy and cheap to implement. Transcription-translation machinery is encapsulated inside of phospholipid vesicles through a process that exploits common instrumentation, such as a centrifugal evaporator and an extruder. Reactions are monitored by fluorescence spectroscopy. The protocols can be adapted for recombinant protein expression, the construction of cellular mimics, the exploration of the minimum requirements for cellular life, or the assembly of genetic circuitry.

The Encapsulation of Cell-free Transcription and Translation Machinery in Vesicles for the Construction of Cellular Mimics

PubMed Central

Spencer, Amy C.; Torre, Paola; Mansy, Sheref S.

2013-01-01

As interest shifts from individual molecules to systems of molecules, an increasing number of laboratories have sought to build from the bottom up cellular mimics that better represent the complexity of cellular life. To date there are a number of paths that could be taken to build compartmentalized cellular mimics, including the exploitation of water-in-oil emulsions, microfluidic devices, and vesicles. Each of the available options has specific advantages and disadvantages. For example, water-in-oil emulsions give high encapsulation efficiency but do not mimic well the permeability barrier of living cells. The primary advantage of the methods described herein is that they are all easy and cheap to implement. Transcription-translation machinery is encapsulated inside of phospholipid vesicles through a process that exploits common instrumentation, such as a centrifugal evaporator and an extruder. Reactions are monitored by fluorescence spectroscopy. The protocols can be adapted for recombinant protein expression, the construction of cellular mimics, the exploration of the minimum requirements for cellular life, or the assembly of genetic circuitry. PMID:24192867

Tunneling-Magnetoresistance Ratio Comparison of MgO-Based Perpendicular-Magnetic-Tunneling-Junction Spin Valve Between Top and Bottom Co2Fe6B2 Free Layer Structure.

PubMed

Lee, Du-Yeong; Lee, Seung-Eun; Shim, Tae-Hun; Park, Jea-Gun

2016-12-01

For the perpendicular-magnetic-tunneling-junction (p-MTJ) spin valve with a nanoscale-thick bottom Co2Fe6B2 free layer ex situ annealed at 400 °C, which has been used as a common p-MTJ structure, the Pt atoms of the Pt buffer layer diffused into the MgO tunneling barrier. This transformed the MgO tunneling barrier from a body-centered cubic (b.c.c) crystallized layer into a mixture of b.c.c, face-centered cubic, and amorphous layers and rapidly decreased the tunneling-magnetoresistance (TMR) ratio. The p-MTJ spin valve with a nanoscale-thick top Co2Fe6B2 free layer could prevent the Pt atoms diffusing into the MgO tunneling barrier during ex situ annealing at 400 °C because of non-necessity of a Pt buffer layer, demonstrating the TMR ratio of ~143 %.

Single-Band and Dual-Band Infrared Detectors

NASA Technical Reports Server (NTRS)

Ting, David Z. (Inventor); Gunapala, Sarath D. (Inventor); Soibel, Alexander (Inventor); Nguyen, Jean (Inventor); Khoshakhlagh, Arezou (Inventor)

2015-01-01

Bias-switchable dual-band infrared detectors and methods of manufacturing such detectors are provided. The infrared detectors are based on a back-to-back heterojunction diode design, where the detector structure consists of, sequentially, a top contact layer, a unipolar hole barrier layer, an absorber layer, a unipolar electron barrier, a second absorber, a second unipolar hole barrier, and a bottom contact layer. In addition, by substantially reducing the width of one of the absorber layers, a single-band infrared detector can also be formed.

Single-Band and Dual-Band Infrared Detectors

NASA Technical Reports Server (NTRS)

Ting, David Z. (Inventor); Gunapala, Sarath D. (Inventor); Soibel, Alexander (Inventor); Nguyen, Jean (Inventor); Khoshakhlagh, Arezou (Inventor)

2017-01-01

Bias-switchable dual-band infrared detectors and methods of manufacturing such detectors are provided. The infrared detectors are based on a back-to-back heterojunction diode design, where the detector structure consists of, sequentially, a top contact layer, a unipolar hole barrier layer, an absorber layer, a unipolar electron barrier, a second absorber, a second unipolar hole barrier, and a bottom contact layer. In addition, by substantially reducing the width of one of the absorber layers, a single-band infrared detector can also be formed.

Properties of perpendicular-anisotropy magnetic tunnel junctions fabricated over the bottom electrode contact

NASA Astrophysics Data System (ADS)

Miura, Sadahiko; Honjo, Hiroaki; Kinoshita, Keizo; Tokutome, Keiichi; Koike, Hiroaki; Ikeda, Shoji; Endoh, Tetsuo; Ohno, Hideo

2015-04-01

Perpendicular-anisotropy magnetic tunnel junctions (MTJs) were prepared on four substrate geometries, i.e., directly on the axis of the bottom electrode contact, directly off the axis of the bottom electrode contact, on the axis of the bottom electrode contact with a polished bottom electrode, and off the axis of the bottom electrode contact with a polished bottom electrode. Electrical shorts were observed for direct on-axis geometry at a certain extent, whereas there were no electrical shorts for the other three geometries. The MR ratio/σR, JC0, and thermal stability factor of the devices for polish on-axis geometry were almost the same as those for polish off-axis geometry. From TEM observations of the polish on-axis device, the interface between the bottom contact and the base electrode was determined to be rough, whereas the MgO barrier layer was determined to be smooth, indicating that the polish process was effective for smooth magnetic tunnel junction fabrication over the bottom contact. MTJs for polish on-axis geometry eliminated the base electrode resistance and increased the magnetoresistance ratio. This technology contributes to the higher density of spin transfer torque magnetic random access memory.

Experimental visualization of the cathode layer in AC surface dielectric barrier discharge

NASA Astrophysics Data System (ADS)

Kim, Sang-You; Lho, Taihyeop; Chung, Kyu-Sun

2018-06-01

A narrow etched polyimide line at the bottom edge of a biased electrode (BE) and a non-etched dielectric surface near the biased electrode were observed in an atmospheric AC flexible surface dielectric barrier discharge of polyimide dielectric. These findings are attributed to the bombardment of positive oxygen ions on the bottom edge of the BE and the electron breakdown trajectory not contacting the polyimide surface following the electric field lines formed between the BE edge and the surface charge layer on the dielectric. The length of the non-etched dielectric surface during the first micro-discharge was observed as 22 μm. This occurred, regardless of three different operating durations, which is in good agreement with the length of the cathode layer according to Paschen's law.

Numerical Analysis of Residual Stress and Distortion Use Finite Element Method on Inner Bottom Construction of Geomarin IV Survey Ship with Welding Sequence Variations

NASA Astrophysics Data System (ADS)

Syahroni, N.; Hartono, A. B. W.; Murtedjo, M.

2018-03-01

In the ship fabrication industry, welding is the most critical stage. If the quality of welding on ship fabrication is not good, then it will affect the strength and overall appearance of the structure. One of the factors that affect the quality of welding is residual stress and distortion. In this research welding simulation is performed on the inner bottom construction of Geomarin IV Ship Survey using shell element and has variation to welding sequence. In this study, welding simulations produced peak temperatures at 2490 K at variation 4. While the lowest peak temperature was produced by variation 2 with a temperature of 2339 K. After welding simulation, it continued simulating residual stresses and distortion. The smallest maximum tensile residual stress found in the inner bottom construction is 375.23 MPa, and the maximum tensile pressure is -20.18 MPa. The residual stress is obtained from variation 3. The distortion occurring in the inner bottom construction for X=720 mm is 4.2 mm and for X=-720 mm, the distortion is 4.92 mm. The distortion is obtained from the variation 3. Near the welding area, distortion value reaches its minimum point. This is because the stiffeners in the form of frames serves as anchoring.

Analysis of administrative barriers in the industry of the high-rise construction in Russian Federation

NASA Astrophysics Data System (ADS)

Zaychenko, Irina; Borremans, Alexandra; Gutman, Svetlana

2018-03-01

The article describes the concept and types of administrative barriers encountered in various areas of the enterprise. The particularities of the Russian high-rise construction industry are described and a comparative analysis of administrative barriers in this sector is performed. The main stages and administrative procedures when the developers implement investment and construction projects in the field of high-rise construction are determined. The regulatory and legal framework for the implementation of investment and project activities in the high-rise construction industry has been studied and conclusions have been drawn on its low level of precision in the issue of the formation of competitive and efficient high-rise construction markets. The average number of administrative procedures for the implementation of the investment and construction project in the field of high-rise construction is determined. The factors preventing the reduction of administrative barriers in the high-rise construction industry are revealed.

Biological effect of low-head sea lamprey barriers: Designs for extensive surveys and the value of incorporating intensive process-oriented research

USGS Publications Warehouse

Hayes, D.B.; Baylis, J.R.; Carl, L.M.; Dodd, H.R.; Goldstein, J.D.; McLaughlin, R.L.; Noakes, D.L.G.; Porto, L.M.

2003-01-01

Four sampling designs for quantifying the effect of low-head sea lamprey (Petromyzon marinus) barriers on fish communities were evaluated, and the contribution of process-oriented research to the overall confidence of results obtained was discussed. The designs include: (1) sample barrier streams post-construction; (2) sample barrier and reference streams post-construction; (3) sample barrier streams pre- and post-construction; and (4) sample barrier and reference streams pre- and post-construction. In the statistical literature, the principal basis for comparison of sampling designs is generally the precision achieved by each design. In addition to precision, designs should be compared based on the interpretability of results and on the scale to which the results apply. Using data collected in a broad survey of streams with and without sea lamprey barriers, some of the tradeoffs that occur among precision, scale, and interpretability are illustrated. Although circumstances such as funding and availability of pre-construction data may limit which design can be implemented, a pre/post-construction design including barrier and reference streams provides the most meaningful information for use in barrier management decisions. Where it is not feasible to obtain pre-construction data, a design including reference streams is important to maintain the interpretability of results. Regardless of the design used, process-oriented research provides a framework for interpreting results obtained in broad surveys. As such, information from both extensive surveys and intensive process-oriented research provides the best basis for fishery management actions, and gives researchers and managers the most confidence in the conclusions reached regarding the effects of sea lamprey barriers.

7. WEST DAM STRUCTURE, LOOKING NORTHWEST. QUARRIES AT BOTTOM; OUTLET ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. WEST DAM STRUCTURE, LOOKING NORTHWEST. QUARRIES AT BOTTOM; OUTLET STRUCTURE UNDER CONSTRUCTION CUTTING INTO HILL AT TOP OF PICTURE. - Eastside Reservoir, Diamond & Domenigoni Valleys, southwest of Hemet, Hemet, Riverside County, CA

30 CFR 77.1605 - Loading and haulage equipment; installations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... passage of wheels. (h) Rocker-bottom or bottom-dump cars shall be equipped with positive locking devices, or other suitable devices. (i) Ramps and dumps shall be of solid construction, of ample width, have...

Electron and hole photoemission detection for band offset determination of tunnel field-effect transistor heterojunctions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Wei; Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics, Peking University, Beijing 100871; Zhang, Qin

2014-11-24

We report experimental methods to ascertain a complete energy band alignment of a broken-gap tunnel field-effect transistor based on an InAs/GaSb hetero-junction. By using graphene as an optically transparent electrode, both the electron and hole barrier heights at the InAs/GaSb interface can be quantified. For a Al{sub 2}O{sub 3}/InAs/GaSb layer structure, the barrier height from the top of the InAs and GaSb valence bands to the bottom of the Al{sub 2}O{sub 3} conduction band is inferred from electron emission whereas hole emissions reveal the barrier height from the top of the Al{sub 2}O{sub 3} valence band to the bottom ofmore » the InAs and GaSb conduction bands. Subsequently, the offset parameter at the broken gap InAs/GaSb interface is extracted and thus can be used to facilitate the development of predicted models of electron quantum tunneling efficiency and transistor performance.« less

EARTHSAWtm IN-SITU CONTAINMENT OF PITS AND TRENCHES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ernest E. Carter, P.E.

2002-09-20

EarthSaw{trademark} is a proposed technology for construction of uniform high quality barriers under and around pits and trenches containing buried radioactive waste without excavating or disturbing the waste. The method works by digging a deep vertical trench around the perimeter of a site, filling that trench with high specific gravity grout sealant, and then cutting a horizontal bottom pathway at the base of the trench with a simple cable saw mechanism. The severed block of earth becomes buoyant in the grout and floats on a thick layer of grout, which then cures into an impermeable barrier. The ''Interim Report onmore » task 1 and 2'' which is incorporated into this report as appendix A, provided theoretical derivations, field validation of formulas, a detailed quantitative engineering description of the technique, engineering drawings of the hardware, and a computer model of how the process would perform in a wide variety of soil conditions common to DOE waste burial sites. The accomplishments of task 1 and 2 are also summarized herein Task 3 work product provides a comprehensive field test plan in Appendix B and a health and safety plan in Appendix C and proposal for a field-scale demonstration of the EarthSaw barrier technology. The final report on the subcontracted stress analysis is provided in Appendix D. A copy of the unified computer model is provided as individual non-functional images of each sheet of the spreadsheet and separately as a Microsoft Excel 2000 file.« less

Bottom friction models for shallow water equations: Manning’s roughness coefficient and small-scale bottom heterogeneity

NASA Astrophysics Data System (ADS)

Dyakonova, Tatyana; Khoperskov, Alexander

2018-03-01

The correct description of the surface water dynamics in the model of shallow water requires accounting for friction. To simulate a channel flow in the Chezy model the constant Manning roughness coefficient is frequently used. The Manning coefficient nM is an integral parameter which accounts for a large number of physical factors determining the flow braking. We used computational simulations in a shallow water model to determine the relationship between the Manning coefficient and the parameters of small-scale perturbations of a bottom in a long channel. Comparing the transverse water velocity profiles in the channel obtained in the models with a perturbed bottom without bottom friction and with bottom friction on a smooth bottom, we constructed the dependence of nM on the amplitude and spatial scale of perturbation of the bottom relief.

Semi top-down method combined with earth-bank, an effective method for basement construction.

NASA Astrophysics Data System (ADS)

Tuan, B. Q.; Tam, Ng M.

2018-04-01

Choosing an appropriate method of deep excavation not only plays a decisive role in technical success, but also in economics of the construction project. Presently, we mainly base on to key methods: “Bottom-up” and “Top-down” construction method. Right now, this paper presents an another method of construction that is “Semi Top-down method combining with earth-bank” in order to take the advantages and limit the weakness of the above methods. The Bottom-up method was improved by using the earth-bank to stabilize retaining walls instead of the bracing steel struts. The Top-down method was improved by using the open cut method for the half of the earthwork quantities.

Evaluation of the performance of portable precast concrete traffic barriers.

DOT National Transportation Integrated Search

1978-01-01

The portable precast concrete traffic barrier is used to separate high speed vehicular traffic and construction activities. However, since there was a lack of information on the barrier's performance in a construction zone environment, officials of t...

The effectiveness of a barrier wall and underpasses in reducing wildlife mortality on a heavily traveled highway in Florida

USGS Publications Warehouse

Dodd, C.K.; Barichivich, W.J.; Smith, L.L.

2004-01-01

Because of high numbers of animals killed on Paynes Prairie State Preserve, Alachua County, Florida, the Florida Department of Transportation constructed a barrier wall-culvert system to reduce wildlife mortality yet allow for passage of some animals across the highway. During a one year study following construction, we counted only 158 animals, excluding hylid treefrogs, killed in the same area where 2411 road kills were recorded in the 12 months prior to the construction of the barrier wall-culvert system. Within the survey area lying directly in Paynes Prairie basin, mortality was reduced 65% if hylid treefrogs are included, and 93.5% with hylid treefrogs excluded. Sixty-four percent of the wildlife kills observed along the barrier wall-culvert system occurred at a maintenance road access point and along 300 m of type-A fence bordering private property. The 24 h kill rate during the post-construction survey was 4.9 compared with 13.5 during the pre-construction survey. We counted 1891 dead vertebrates within the entire area surveyed, including the ecotone between the surrounding uplands and prairie basin which did not include the barrier wall and culverts. Approximately 73% of the nonhylid road kills occurred in the 400 m section of road beyond the extent of the barrier wall-culvert system. We detected 51 vertebrate species, including 9 fish, using the 8 culverts after the construction of the barrier wall-culvert system, compared with 28 vertebrate species in the 4 existing culverts prior to construction. Capture success in culverts increased 10-fold from the pre-construction survey to the post-construction survey. Barrier wall trespass was facilitated by overhanging vegetation, maintenance road access, and by the use of the type-A fence. Additional problems resulted from siltation, water holes, and human access. These problems could be corrected using design modifications and by routine, periodic maintenance.

Monitoring changes in stream bottom sediments and benthic invertebrates.

DOT National Transportation Integrated Search

1981-01-01

The study was conducted to determine whether the analysis of stream bottom sediments could be used to assess sediment pollution generated by highway construction. Most of the work completed to date has involved testing and refining methods for the co...

Fabrication of metallic single electron transistors featuring plasma enhanced atomic layer deposition of tunnel barriers

NASA Astrophysics Data System (ADS)

Karbasian, Golnaz

The continuing increase of the device density in integrated circuits (ICs) gives rise to the high level of power that is dissipated per unit area and consequently a high temperature in the circuits. Since temperature affects the performance and reliability of the circuits, minimization of the energy consumption in logic devices is now the center of attention. According to the International Technology Roadmaps for Semiconductors (ITRS), single electron transistors (SETs) hold the promise of achieving the lowest power of any known logic device, as low as 1x10-18 J per switching event. Moreover, SETs are the most sensitive electrometers to date, and are capable of detecting a fraction of an electron charge. Despite their low power consumption and high sensitivity for charge detection, room temperature operation of these devices is quite challenging mainly due to lithographical constraints in fabricating structures with the required dimensions of less than 10 nm. Silicon based SETs have been reported to operate at room temperature. However, they all suffer from significant variation in batch-to-batch performance, low fabrication yield, and temperature-dependent tunnel barrier height. In this project, we explored the fabrication of SETs featuring metal-insulator-metal (MIM) tunnel junctions. While Si-based SETs suffer from undesirable effect of dopants that result in irregularities in the device behavior, in metal-based SETs the device components (tunnel barrier, island, and the leads) are well-defined. Therefore, metal SETs are potentially more predictable in behavior, making them easier to incorporate into circuits, and easier to check against theoretical models. Here, the proposed fabrication method takes advantage of unique properties of chemical mechanical polishing (CMP) and plasma enhanced atomic layer deposition (PEALD). Chemical mechanical polishing provides a path for tuning the dimensions of the tunnel junctions, surpassing the limits imposed by electron beam lithography and lift-off, while atomic layer deposition provides precise control over the thickness of the tunnel barrier and significantly increases the choices for barrier materials. As described below in detail, the fabrication of ultra-thin (~1nm) tunnel transparent barriers with PEALD is in fact challenging; we demonstrate that in fabrication of SETs with PEALD to form the barrier in the Ni-insulator-Ni tunnel junctions, additional NiO layers are parasitically formed in the Ni layers that form the top and bottom electrodes of the tunnel junctions. The NiO on the bottom electrode is formed due to oxidizing effect of the O 2 plasma used in the PEALD process, while the NiO on the bottom of the top electrode is believed to form during the metal deposition due to oxygen-containing contaminants on the surface of the deposited tunnel barrier. We also show that due to the presence of these surface parasitic layers of NiO, the resistance of Ni-insulator-Ni tunnel junctions is drastically increased. Moreover, the transport mechanism is changed from quantum tunneling through the dielectric barrier to one consistent with the tunnel barrier in series with compound layers of NiO and possibly, NiSixOy. The parasitic component in the tunnel junctions results in conduction freeze-out at low temperatures, deviation of junction parameters from ideal model, and excessive noise in the device. The reduction of NiO to Ni is therefore necessary to restore the metal-insulator-metal structure of the junctions. We have studied forming gas anneal as well as H2 plasma treatment as techniques to reduce the NiO layers that are parasitically formed in the junctions. Using either of these two techniques, we reduced the NiO formed on the island after being covered with the PEALD dielectric and before defining the top source and drain. Later, the NiO formed on the bottom of the source/drain is reduced during a second reducing step after the source/drain are formed on the tunnel barrier. Electrical characterization of SETs that are made with the proposed reducing treatments enable us to study the effect of each reducing process on the properties of the constituent tunnel junctions. In comparison to the junctions annealed twice in forming gas at 400°C, we consistently observed a ~10x higher conductance in devices treated twice with H2 plasma at 300°C. The possible damage to the barrier during the plasma treatment and thermally induced film deformation during the anneal which respectively, is believed to increase and lower the conductance are among the possible cause of this difference. Although both types of treatments were effective in alleviating the effect of the activated components in the junctions, all the devices that were treated by two anneal steps or by two H2 plasma steps (for reducing the top and bottom NiO) show deviations from ideal simulated MIM SET model and suffer from significant random telegraph signal (RTS) noise. However, our results show that by using forming gas anneal for bottom NiO reduction and H2 plasma for the top NiO reduction, one can achieve devices close to ideal MIM SETs with significantly less noise.

Recommendations for Constructing Roadside Vegetation Barriers to Improve Near-Road Air Quality

EPA Pesticide Factsheets

The EPA report, Recommendations for Constructing Roadside Vegetation Barriers to Improve Near-Road Air Quality, summarizes the research findings on the best practices for building roadside vegetative barriers to improve air quality. This fact sheet describ

Drywall construction as a dental radiation barrier

DOE Office of Scientific and Technical Information (OSTI.GOV)

MacDonald, J.C.; Reid, J.A.; Berthoty, D.

1983-03-01

Six typical forms of drywall construction have been tested as barriers against primary and secondary dental x-radiation. It is concluded that this widely used type of wall construction is generally effective for this purpose, but with a heavy workload two thicknesses of wallboard on each side of the wall are required to provide a sufficient barrier. In general, no lead need be incorporated in the walls.

Drywall construction as a dental radiation barrier.

PubMed

MacDonald, J C; Reid, J A; Berthoty, D

1983-03-01

Six typical forms of drywall construction have been tested as barriers against primary and secondary dental x-radiation. It is concluded that this widely used type of wall construction is generally effective for this purpose, but with a heavy workload two thicknesses of wallboard on each side of the wall are required to provide a sufficient barrier. In general, no lead need be incorporated in the walls.

Sensor System Fo4r Buried Waste Containment Sites

DOEpatents

Smith, Ann Marie; Gardner, Bradley M.; Kostelnik, Kevin M.; Partin, Judy K.; Lancaster, Gregory D.; Pfeifer, Mary Catherine

2003-11-18

A sensor system for a buried waste containment site having a bottom wall barrier and sidewall barriers, for containing hazardous waste. The sensor system includes one or more sensor devices disposed in one or more of the barriers for detecting a physical parameter either of the barrier itself or of the physical condition of the surrounding soils and buried waste, and for producing a signal representing the physical parameter detected. Also included is a signal processor for receiving signals produced by the sensor device and for developing information identifying the physical parameter detected, either for sounding an alarm, displaying a graphic representation of a physical parameter detected on a viewing screen and/or a hard copy printout. The sensor devices may be deployed in or adjacent the barriers at the same time the barriers are deployed and may be adapted to detect strain or cracking in the barriers, leakage of radiation through the barriers, the presence and leaking through the barriers of volatile organic compounds, or similar physical conditions.

Sensor system for buried waste containment sites

DOEpatents

Smith, Ann Marie; Gardner, Bradley M.; Kostelnik, Kevin M.; Partin, Judy K.; Lancaster, Gregory D.; Pfeifer, May Catherine

2000-01-01

A sensor system is disclosed for a buried waste containment site having a bottom wall barrier and/or sidewall barriers, for containing hazardous waste. The sensor system includes one or more sensor devices disposed in one or more of the barriers for detecting a physical parameter either of the barrier itself or of the physical condition of the surrounding soils and buried waste, and for producing a signal representing the physical parameter detected. Also included is a signal processor for receiving signals produced by the sensor device and for developing information identifying the physical parameter detected, either for sounding an alarm, displaying a graphic representation of a physical parameter detected on a viewing screen and/or a hard copy printout. The sensor devices may be deployed in or adjacent the barriers at the same time the barriers are deployed and may be adapted to detect strain or cracking in the barriers, leakage of radiation through the barriers, the presence and leaking through the barriers of volatile organic compounds, or similar physical conditions.

Sensor System Fo4r Buried Waste Containment Sites

DOEpatents

Smith, Ann Marie; Gardner, Bradley M.; Kostelnik, Kevin M.; Partin, Judy K.; Lancaster, Gregory D.; Pfeifer, Mary Catherine

2005-09-27

A sensor system for a buried waste containment site having a bottom wall barrier and/or sidewall barriers, for containing hazardous waste. The sensor system includes one or more sensor devices disposed in one or more of the barriers for detecting a physical parameter either of the barrier itself or of the physical condition of the surrounding soils and buried waste, and for producing a signal representing the physical parameter detected. Also included is a signal processor for receiving signals produced by the sensor device and for developing information identifying the physical parameter detected, either for sounding an alarm, displaying a graphic representation of a physical parameter detected on a viewing screen and/or a hard copy printout. The sensor devices may be deployed in or adjacent the barriers at the same time the barriers are deployed and may be adapted to detect strain or cracking in the barriers, leakage of radiation through the barriers, the presence and leaking through the barriers of volatile organic compounds, or similar physical conditions.

MHD program plan, FY 1991

NASA Astrophysics Data System (ADS)

1990-10-01

The current magnetohydrodynamic MHD program being implemented is a result of a consensus established in public meetings held by the Department of Energy in 1984. The public meetings were followed by the formulation of a June 1984 Coal-Fired MHD Preliminary Transition and Program Plan. This plan focused on demonstrating the proof-of-concept (POC) of coal-fired MHD electric power plants by the early 1990s. MHD test data indicate that while there are no fundamental technical barriers impeding the development of MHD power plants, technical risk remains. To reduce the technical risk three key subsystems (topping cycle, bottoming cycle, and seed regeneration) are being assembled and tested separately. The program does not require fabrication of a complete superconducting magnet, but rather the development and testing of superconductor cables. The topping cycle system test objectives can be achieved using a conventional iron core magnet system already in place at a DOE facility. Systems engineering-derived requirements and analytical modeling to support scale-up and component design guide the program. In response to environmental, economic, engineering, and utility acceptance requirements, design choices and operating modes are tested and refined to provide technical specifications for meeting commercial criteria. These engineering activities are supported by comprehensive and continuing systems analyses to establish realistic technical requirements and cost data. Essential elements of the current program are to: develop technical and environmental data for the integrated MHD topping cycle and bottoming cycle systems through POC testing (1000 and 4000 hours, respectively); design, construct, and operate a POC seed regeneration system capable of processing spent seed materials from the MHD bottoming cycle; prepare conceptual designs for a site specific MHD retrofit plant; and continue supporting research necessary for system testing.

Monotonic aspects of the mechanical behaviour of bottom ash from municipal solid waste incineration and its potential use for road construction.

PubMed

Becquart, Frederic; Bernard, Fabrice; Abriak, Nor Edine; Zentar, Rachid

2009-04-01

Municipal solid waste incineration (MSWI) bottom ash is an atypical granular material because it may include industrial by-products that result from the incineration of domestic waste. The prospects for the beneficial use of this particular material mainly lie in the field of road construction, as a substitute for the traditional natural aggregates. However, its mechanical properties are still little known, particularly in term of stiffness and deformability, characteristics that are essential to the construction of a durable roadway. The purpose of this paper is to describe better the mechanical behaviour of this recycled material. In order to reach this objective, a large experimental campaign is presented. The first part of this paper presents and comments in detail on the results obtained from static monotonic tests. Oedometric and triaxial shear tests were performed on MSWI bottom ash both before and after treatment with a specific hydraulic binder. These tests allow specification of the mechanical characteristics of the MSWI bottom ash, such as the initial Young's modulus, Poisson's ratio, the compressibility index, the friction angle, and the contracting or dilating behaviour of the material. The results reveal a mechanical behaviour similar to that of initially dense standard materials (sands, unbound granular materials) and a dependence on the applied average pressure, characteristic of the mechanical behaviour of granular media. More laboratory data on other samples of MSWI bottom ash are required to ensure that this comparison is statistically valid.

49 CFR 587.17 - Construction.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 7 2012-10-01 2012-10-01 false Construction. 587.17 Section 587.17 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) DEFORMABLE BARRIERS Offset Deformable Barrier § 587.17 Construction...

49 CFR 587.17 - Construction.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 7 2014-10-01 2014-10-01 false Construction. 587.17 Section 587.17 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) DEFORMABLE BARRIERS Offset Deformable Barrier § 587.17 Construction...

49 CFR 587.17 - Construction.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 7 2011-10-01 2011-10-01 false Construction. 587.17 Section 587.17 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) DEFORMABLE BARRIERS Offset Deformable Barrier § 587.17 Construction...

49 CFR 587.17 - Construction.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 7 2013-10-01 2013-10-01 false Construction. 587.17 Section 587.17 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) DEFORMABLE BARRIERS Offset Deformable Barrier § 587.17 Construction...

Bottom-up GGM algorithm for constructing multiple layered hierarchical gene regulatory networks

USDA-ARS?s Scientific Manuscript database

Multilayered hierarchical gene regulatory networks (ML-hGRNs) are very important for understanding genetics regulation of biological pathways. However, there are currently no computational algorithms available for directly building ML-hGRNs that regulate biological pathways. A bottom-up graphic Gaus...

Sedimentology of gravelly Lake Lahontan highstand shoreline deposits, Churchill Butte, Nevada, USA

NASA Astrophysics Data System (ADS)

Blair, Terence C.

1999-02-01

Gravelly shoreline deposits of the latest Pleistocene highstand of Lake Lahontan occur in pristine depositional morphology, and are exposed in gravel pits along Churchill Butte in west-central Nevada. Four environments differentiated at this site are alluvial fan/colluvium, lakeshore barrier spit, lake lower-shoreface spit platform, and lake bottom. Lakeshore deposits abut, along erosional wave headcuts, either unsorted muddy to bouldery colluvium fringing Churchill Butte bedrock, or matrix-supported, cobbly and pebbly debris-flow deposits of the Silver Springs fan. The lakeshore barrier spit is dominated by granule pebble gravel concentrated by wave erosion of the colluvial and alluvial-fan facies. The lakeward side of the barrier consists of beachface deposits of well-sorted granules or pebbles in broad, planar beds 1-10 cm thick and sloping 10-15°. They interfinger downslope with thicker (10-25 cm) and less steep (5-10°) lakeward-dipping beds of fine to medium pebble gravel of the lake upper shoreface. Interstratified with the latter are 10-40-cm-thick sets of high-angle cross-beds that dip southward, alongshore. Higher-angle (15-20°), landward-dipping foresets of similar texture but poorer sorting comprise the proximal backshore on the landward side of the barrier. They were deposited during storm surges that overtopped the barrier berm. Gastropod-rich sand and mud, also deposited by storm-induced washover, are found landward of the gravel foresets in a 15-m-wide backshore pond. Algal stromatolites, ostracodes, and diatoms accumulated in this pond between storm events. The lake lower shoreface, extending from water depths of 2 to 8 m, consists of a southward-prograding spit platform built by longshore drift. The key component of this platform is large-scale sandy pebble gravel in 16° southward-dipping `Gilbert' foresets that grade at a water depth of about 6-7 m to 4°-dipping sandy toesets. A shift from bioturbated lower-shoreface sand and silt, to flat and laminated lake-bottom silt and mud, occurs between water depths of 10-40 m and over a shore-normal distance of ≥250 m. This lake-bottom mud facies, unlike the others, is areally expansive.

Oblique wave trapping by vertical permeable membrane barriers located near a wall

NASA Astrophysics Data System (ADS)

Koley, Santanu; Sahoo, Trilochan

2017-12-01

The effectiveness of a vertical partial flexible porous membrane wave barrier located near a rigid vertical impermeable seawall for trapping obliquely incident surface gravity waves are analyzed in water of uniform depth under the assumption of linear water wave theory and small amplitude membrane barrier response. From the general formulation of the submerged membrane barrier, results for bottom-standing and surface-piercing barriers are computed and analyzed in special cases. Using the eigenfunction expansion method, the boundary-value problems are converted into series relations and then the required unknowns are obtained using the least squares approximation method. Various physical quantities of interests like reflection coefficient, wave energy dissipation, wave forces acting on the membrane barrier and the seawall are computed and analyzed for different values of the wave and structural parameters. The study will be useful in the design of the membrane wave barrier for the creation of tranquility zone in the lee side of the barrier to protect the seawall.

Robotic Telesurgery Research

DTIC Science & Technology

2009-03-01

closed (right) positions. The upper jaw is constructed out of a super-elastic shape- memory nickel titanium alloy ( Nitinol ) ribbon (Memry Corporation...tissue. The Nitinol ribbon is glued to a fixed nylon rod insert that fits inside the bottom jaw. The nylon rod is also glued to the bottom jaw, and...configurations (bottom). The two collar pieces are connected to one another by two 0.12 mm thick Nitinol ribbons that are anchored to the collar walls. A

The effects of stream channelization on bottom dwelling organisms : phase 2 report : 1975 construction season.

DOT National Transportation Integrated Search

1976-01-01

Three construction projects affecting streams are being monitored. On two of the projects, those affecting Meadow Run and Moores Creek, the streams are being monitored for flow, suspended solids, rainfall, and benthic populations. Construction has be...

An integrative top-down and bottom-up qualitative model construction framework for exploration of biochemical systems.

PubMed

Wu, Zujian; Pang, Wei; Coghill, George M

Computational modelling of biochemical systems based on top-down and bottom-up approaches has been well studied over the last decade. In this research, after illustrating how to generate atomic components by a set of given reactants and two user pre-defined component patterns, we propose an integrative top-down and bottom-up modelling approach for stepwise qualitative exploration of interactions among reactants in biochemical systems. Evolution strategy is applied to the top-down modelling approach to compose models, and simulated annealing is employed in the bottom-up modelling approach to explore potential interactions based on models constructed from the top-down modelling process. Both the top-down and bottom-up approaches support stepwise modular addition or subtraction for the model evolution. Experimental results indicate that our modelling approach is feasible to learn the relationships among biochemical reactants qualitatively. In addition, hidden reactants of the target biochemical system can be obtained by generating complex reactants in corresponding composed models. Moreover, qualitatively learned models with inferred reactants and alternative topologies can be used for further web-lab experimental investigations by biologists of interest, which may result in a better understanding of the system.

Reduction of Leaching Impacts by Applying Biomass Bottom Ash and Recycled Mixed Aggregates in Structural Layers of Roads

PubMed Central

Cabrera, Manuel; Galvin, Adela P.; Agrela, Francisco; Beltran, Manuel G.; Ayuso, Jesus

2016-01-01

This research is focused on analyzing the environmental pollution potential of biomass bottom ashes as individual materials, as mixtures manufactured with biomass bottom ashes and granular construction aggregates, and these mixtures treated with cement. For the environmental assessment of all of the samples and materials mentioned, the following leaching procedures have been performed: the compliance batch test of UNE-EN 12457-3:2003 for aggregates and bottom ashes; the column test according to NEN 7343:1994 for the mixtures prepared in the laboratory; and the tank test by EA NEN 7375:2004 for analyzing the behavior of mixtures after their solidification/stabilization with 5% cement. After the discussion of the data, the reduction of the pollution load of the most hazardous biomass bottom ashes after their combination with different aggregates can be confirmed, which implies their possible application in civil infrastructures, such as filler embankments and road construction layers, without negatively impacting the environment. In addition, the positive effect of the stabilization/solidification of the cement-treated mixtures with a reduction of the heavy metals that were released at the highest levels, namely As, Hg Cr, Ni, Cu, Se and Mo, was proven. PMID:28773352

Electrical transport across nanometric SrTiO3 and BaTiO3 barriers in conducting/insulator/conducting junctions

NASA Astrophysics Data System (ADS)

Navarro, H.; Sirena, M.; González Sutter, J.; Troiani, H. E.; del Corro, P. G.; Granell, P.; Golmar, F.; Haberkorn, N.

2018-01-01

We report the electrical transport properties of conducting/insulator/conducting heterostructures by studying current-voltage IV curves at room temperature. The measurements were obtained on tunnel junctions with different areas (900, 400 and 100 μm2) using a conducting atomic force microscope. Trilayers with GdBa2Cu3O7 (GBCO) as the bottom electrode, SrTiO3 or BaTiO3 (thicknesses between 1.6 and 4 nm) as the insulator barrier, and GBCO or Nb as the top electrode were grown by DC sputtering on (100) SrTiO3 substrates For SrTiO3 and BaTiO3 barriers, asymmetric IV curves at positive and negative polarization can be obtained using electrodes with different work function. In addition, hysteretic IV curves are obtained for BaTiO3 barriers, which can be ascribed to a combined effect of the FE reversal switching polarization and an oxygen vacancy migration. For GBCO/BaTiO3/GBCO heterostructures, the IV curves correspond to that expected for asymmetric interfaces, which indicates that the disorder affects differently the properties at the bottom and top interfaces. Our results show the role of the interface disorder on the electrical transport of conducting/insulator/conduction heterostructures, which is relevant for different applications, going from resistive switching memories (at room temperature) to Josephson junctions (at low temperatures).

23 CFR 772.13 - Federal participation.

Code of Federal Regulations, 2011 CFR

2011-04-01

... property rights (either in fee or lesser interest) for construction of noise barriers. (4) Construction of noise barriers (including landscaping for aesthetic purposes) whether within or outside the highway... ABATEMENT OF HIGHWAY TRAFFIC NOISE AND CONSTRUCTION NOISE § 772.13 Federal participation. (a) Federal funds...

Physical habitat dynamics in four side-channel chutes, lower Missouri River

USGS Publications Warehouse

Jacobson, Robert B.; Johnson, Harold E.; Laustrup, Mark S.; D'Urso, Gary J.; Reuter, Joanna M.

2004-01-01

Construction of the side-channel chutes has become a popular means to rehabilitate habitate of the Lower Missouri River. We studied various aspects of hydrology, hydraulics, and geomorphology of four side-channel chutes to document a range of existing conditions in the Lower Missouri River. The Cranberry Bend side-channel chute has existed for at least 40 years and is an example of a persistent, minimally engineered chute. The Lisbon Bottom side-channel chute is a young chute, created by extreme floods during 1993-1996, and allowed to evolve with minimum engineering of inlet and outlet structures. The Hamburg Bend and North Overton Bottom side-channel chutes were constructed in 1996 and 2000, respectively, as part of the Missouri River Bank Stabilization and navigation Fish and Wildlife Mitigation Project. These side-channel chutes provide increased areas of sandbars and shallow, slow water -- habitats thought to be substantially diminished in the modern Missouri River. Depths and velocities measured in side-channel chutes are also present in the main channel, but the chutes provide more areas of slow, shallow water and they increase the range of discharges over which shallow, slow water is present. The 3.6 km long Lisbon Bottom chute provides as much as 50% of the entire shallow water habitat that exists in the encompassing 15 km reach of the river. At Cranberry Bend and Lisbon Bottom, the side-channel chutes provided 10-40% of the availabile sandbar area in the reach, depending on discharge. Each of the side-channel chutes shows evidence of continuing erosion and deposition. The longevity and the Cranberry Bend chute attests to dynamic stability -- that is, a chute that maintains form and processes while shifting in position. The Hamburg chute similarly shows evidence of lateral movement and construction of flood plain to compensate for erosion. The Lisbon Bottom chute -- the most intensively studied chute -- appears to have achieved an equilibrium width and continues to migrate slowly; however, evidence of aggradation indicates that the chute has not reached an ultimate form, and may be continuing to adjust to altered hydrology and sediment availability. The North Overton Bottoms chute is the newest in the study. In its originally constructed form, the North Overton Bottoms pilot chute was extremely stable, even while being subjected to two floods in excess of 2-year recurrence interval and after accumulating large, potentially destabilizing large woody debris jams. Ongoing adaptive re-engineering of the North Overton Bottoms chute has prevented assessment of how the chute might have adjusted its form in the absence of intervention.

40 CFR 265.1100 - Applicability.

Code of Federal Regulations, 2013 CFR

2013-07-01

...: (1) A primary barrier designed and constructed of materials to prevent migration of hazardous... constructed of materials to prevent migration of hazardous constituents into the barrier, with a leak...

40 CFR 265.1100 - Applicability.

Code of Federal Regulations, 2014 CFR

2014-07-01

...: (1) A primary barrier designed and constructed of materials to prevent migration of hazardous... constructed of materials to prevent migration of hazardous constituents into the barrier, with a leak...

40 CFR 265.1100 - Applicability.

Code of Federal Regulations, 2012 CFR

2012-07-01

...: (1) A primary barrier designed and constructed of materials to prevent migration of hazardous... constructed of materials to prevent migration of hazardous constituents into the barrier, with a leak...

40 CFR 265.1100 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-07-01

...: (1) A primary barrier designed and constructed of materials to prevent migration of hazardous... constructed of materials to prevent migration of hazardous constituents into the barrier, with a leak...

40 CFR 265.1100 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-07-01

...: (1) A primary barrier designed and constructed of materials to prevent migration of hazardous... constructed of materials to prevent migration of hazardous constituents into the barrier, with a leak...

A Study of Baroclinic Instability Induced Convergence Near the Bottom Using Water Age Simulations

NASA Astrophysics Data System (ADS)

Zhang, Wenxia; Hetland, Robert D.

2018-03-01

Baroclinic instability of lateral density gradients gives way to lateral buoyancy transport, which often results in convergence of buoyancy transport. Along a sloping bottom, the induced convergence can force upward extension of bottom water. Eddy transport induced convergence at the bottom and the consequent suspended layers of bottom properties are investigated using a three-dimensional idealized model. Motivated by the distinct characteristics of intrusions over the Texas-Louisiana shelf, a series of configurations are performed with the purpose of identifying parameter impacts on the intensity of eddy transport. This study uses the "horizontal slope Burger number" as the predominant parameter; the parameter is functioned with SH=SRi-1/2=δ/Ri to identify formation of baroclinic instability, where S is the slope Burger number, δ is the slope parameter, and Ri is the Richardson number, previously shown to be the parameter that predicts the intensity of baroclinic instability on the shelf. Intrusion spreads into the interior abutting a layer that is characterized by degraded vertical stratification; a thickening in the bottom boundary layer colocates with the intrusion, which usually thins at either edge of the intrusion because of a density barrier in association with concentrated isopycnals. The intensity of convergence degrades and bottom tracer fluxes reduce linearly with increased SH on logarithmic scales, and the characteristics of bottom boundary layer behavior and the reversal in alongshore current tend to vanish.

46 CFR 91.55-5 - Plans and specifications required for new construction.

Code of Federal Regulations, 2010 CFR

2010-10-01

... systems. (e) Marine engineering. For plans required for marine engineering equipment and systems, see... electrical engineering, equipment and systems, see subchapter J (Electrical Engineering) of this chapter. (g... bottoms, etc., and including inboard and outboard profile. (b) Hull structure. 1 (1) *Inner Bottom Plating...

Improvement of Self-Heating of Indium Gallium Zinc Aluminum Oxide Thin-Film Transistors Using Al2O3 Barrier Layer

NASA Astrophysics Data System (ADS)

Jian, Li-Yi; Lee, Hsin-Ying; Lin, Yung-Hao; Lee, Ching-Ting

2018-02-01

To study the self-heating effect, aluminum oxide (Al2O3) barrier layers of various thicknesses have been inserted between the channel layer and insulator layer in bottom-gate-type indium gallium zinc aluminum oxide (IGZAO) thin-film transistors (TFTs). Each IGZAO channel layer was deposited on indium tin oxide (ITO)-coated glass substrate by using a magnetron radiofrequency cosputtering system with dual targets composed of indium gallium zinc oxide (IGZO) and Al. The 3 s orbital of Al cation provided an extra transport pathway and widened the conduction-band bottom, thus increasing the electron mobility of the IGZAO films. The Al-O bonds were able to sustain the oxygen stability of the IGZAO films. The self-heating behavior of the resulting IGZAO TFTs was studied by Hall measurements on the IGZAO films as well as the electrical performance of the IGZAO TFTs with Al2O3 barrier layers of various thicknesses at different temperatures. IGZAO TFTs with 50-nm-thick Al2O3 barrier layer were stressed by positive gate bias stress (PGBS, at gate-source voltage V GS = 5 V and drain-source voltage V DS = 0 V); at V GS = 5 V and V DS = 10 V, the threshold voltage shifts were 0.04 V and 0.2 V, respectively, much smaller than for the other IGZAO TFTs without Al2O3 barrier layer, which shifted by 0.2 V and 1.0 V when stressed under the same conditions.

Design and validation of a microfluidic device for blood-brain barrier monitoring and transport studies

NASA Astrophysics Data System (ADS)

Ugolini, Giovanni Stefano; Occhetta, Paola; Saccani, Alessandra; Re, Francesca; Krol, Silke; Rasponi, Marco; Redaelli, Alberto

2018-04-01

In vitro blood-brain barrier models are highly relevant for drug screening and drug development studies, due to the challenging task of understanding the transport mechanism of drug molecules through the blood-brain barrier towards the brain tissue. In this respect, microfluidics holds potential for providing microsystems that require low amounts of cells and reagent and can be potentially multiplexed for increasing the ease and throughput of the drug screening process. We here describe the design, development and validation of a microfluidic device for endothelial blood-brain barrier cell transport studies. The device comprises of two microstructured layers (top culture chamber and bottom collection chamber) sandwiching a porous membrane for the cell culture. Microstructured layers include two pairs of physical electrodes, embedded into the device layers by geometrically defined guiding channels with computationally optimized positions. These electrodes allow the use of commercial electrical measurement systems for monitoring trans-endothelial electrical resistance (TEER). We employed the designed device for performing preliminary assessment of endothelial barrier formation with murine brain endothelial cells (Br-bEnd5). Results demonstrate that cellular junctional complexes effectively form in the cultures (expression of VE-Cadherin and ZO-1) and that the TEER monitoring systems effectively detects an increase of resistance of the cultured cell layers indicative of tight junction formation. Finally, we validate the use of the described microsystem for drug transport studies demonstrating that Br-bEnd5 cells significantly hinder the transport of molecules (40 kDa and 4 kDa dextran) from the top culture chamber to the bottom collection chamber.

Stimulation of methane oxidation potential and effects on vegetation growth by bottom ash addition in a landfill final evapotranspiration cover.

PubMed

Kim, Gil Won; Ho, Adrian; Kim, Pil Joo; Kim, Sang Yoon

2016-09-01

The landfilling of municipal solid waste is a significant source of atmospheric methane (CH4), contributing up to 20% of total anthropogenic CH4 emissions. The evapotranspiration (ET) cover system, an alternative final cover system in waste landfills, has been considered to be a promising way to mitigate CH4 emissions, as well as to prevent water infiltration using vegetation on landfill cover soils. In our previous studies, bottom ash from coal-fired power plants was selected among several industrial residues (blast furnace slag, bottom ash, construction waste, steel manufacture slag, stone powder sludge, and waste gypsum) as the best additive for ET cover systems, with the highest mechanical performance achieved for a 35% (wtwt(-1)) bottom ash content in soil. In this study, to evaluate the field applicability of bottom ash mixed soil as ET cover, four sets of lysimeters (height 1.2m×width 2m×length 6m) were constructed in 2007, and four different treatments were installed: (i) soil+bottom ash (35% wtwt(-1)) (SB); (ii) soil+compost (2% wtwt(-1), approximately corresponding to 40Mgha(-1) in arable field scale) (SC); (iii) soil+bottom ash+compost (SBC); and (iv) soil only as the control (S). The effects of bottom ash mixing in ET cover soil on CH4 oxidation potential and vegetation growth were evaluated in a pilot ET cover system in the 5th year after installation by pilot experiments using the treatments. Our results showed that soil properties were significantly improved by bottom ash mixing, resulting in higher plant growth. Bottom ash addition significantly increased the CH4 oxidation potential of the ET cover soil, mainly due to improved organic matter and available copper concentration, enhancing methanotrophic abundances in soil amended with bottom ash. Conclusively, bottom ash could be a good alternative as a soil additive in the ET cover system to improve vegetation growth and mitigate CH4 emission impact in the waste landfill system. Copyright © 2016 Elsevier Ltd. All rights reserved.

Room-temperature solution-processed and metal oxide-free nano-composite for the flexible transparent bottom electrode of perovskite solar cells

NASA Astrophysics Data System (ADS)

Lu, Haifei; Sun, Jingsong; Zhang, Hong; Lu, Shunmian; Choy, Wallace C. H.

2016-03-01

The exploration of low-temperature and solution-processed charge transporting and collecting layers can promote the development of low-cost and large-scale perovskite solar cells (PVSCs) through an all solution process. Here, we propose a room-temperature solution-processed and metal oxide-free nano-composite composed of a silver nano-network and graphene oxide (GO) flawless film for the transparent bottom electrode of a PVSC. Our experimental results show that the amount of GO flakes play a critical role in forming the flawless anti-corrosive barrier in the silver nano-network through a self-assembly approach under ambient atmosphere, which can effectively prevent the penetration of liquid or gaseous halides and their corrosion against the silver nano-network underneath. Importantly, we simultaneously achieve good work function alignment and surface wetting properties for a practical bottom electrode by controlling the degree of reduction of GO flakes. Finally, flexible PVSC adopting the room-temperature and solution-processed nano-composite as the flexible transparent bottom electrode has been demonstrated on a polyethylene terephthalate (PET) substrate. As a consequence, the demonstration of our room-temperature solution-processed and metal oxide-free flexible transparent bottom electrode will contribute to the emerging large-area flexible PVSC technologies.The exploration of low-temperature and solution-processed charge transporting and collecting layers can promote the development of low-cost and large-scale perovskite solar cells (PVSCs) through an all solution process. Here, we propose a room-temperature solution-processed and metal oxide-free nano-composite composed of a silver nano-network and graphene oxide (GO) flawless film for the transparent bottom electrode of a PVSC. Our experimental results show that the amount of GO flakes play a critical role in forming the flawless anti-corrosive barrier in the silver nano-network through a self-assembly approach under ambient atmosphere, which can effectively prevent the penetration of liquid or gaseous halides and their corrosion against the silver nano-network underneath. Importantly, we simultaneously achieve good work function alignment and surface wetting properties for a practical bottom electrode by controlling the degree of reduction of GO flakes. Finally, flexible PVSC adopting the room-temperature and solution-processed nano-composite as the flexible transparent bottom electrode has been demonstrated on a polyethylene terephthalate (PET) substrate. As a consequence, the demonstration of our room-temperature solution-processed and metal oxide-free flexible transparent bottom electrode will contribute to the emerging large-area flexible PVSC technologies. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr00011h

INVESTIGATION OF RECYCLED TIRE CHIPS FOR USE IN GDOT CONCRETE USED TO CONSTRUCT BARRIER WALLS AND OTHER APPLIATIONS–PHASE I

DOT National Transportation Integrated Search

2017-09-01

In 2013, GDOT constructed more than 42,000 LF of concrete barrier utilizing a Class A concrete mixture design (3000 psi). There may be potential for the beneficial utilization of recycled tire chips in concrete barrier applications which can possibly...

Thermography Control of Heat Insulation and Tightness of Buildings,

DTIC Science & Technology

1980-11-01

drawing, top to bottom: 100 + 50 mm mineral wool panels, bulk density 50 kg/m3 Vapor barrier of plastic foil 3/4" tongue and groove 13 mm gypsum panel...Horizontal steel bolts Horisontella Air leakage, in A Ireqlar Corrugated sheet metal 90 mm mineral wool (with sheathing paper) Ko"mir) emd 30 mm mineral ...bolt; Outward leakage of warm air from the room; Steel siding; 90 mm mineral wool (with wind protection); 30 mm mineral wool (with vapor barrier

Bottom-up heating method for producing polyethylene lunar concrete in lunar environment

NASA Astrophysics Data System (ADS)

Lee, Jaeho; Ann, Ki Yong; Lee, Tai Sik; Mitikie, Bahiru Bewket

2018-07-01

The Apollo Program launched numerous missions to the Moon, Earth's nearest and only natural satellite. NASA is now planning new Moon missions as a first step toward human exploration of Mars and other planets. However, the Moon has an extreme environment for humans. In-situ resource utilization (ISRU) construction must be used on the Moon to build habitable structures. Previous studies on polymeric lunar concrete investigated top-down heating for stabilizing the surface. This study investigates bottom-up heating with manufacturing temperatures as low as 200 °C in a vacuum chamber that simulates the lunar environment. A maximum compressive strength of 5.7 MPa is attained; this is suitable for constructing habitable structures. Furthermore, the bottom-up heating approach achieves solidification two times faster than does the top-down heating approach.

Characteristics of depositional environments in the Nakdong River Estuary, South Korea

NASA Astrophysics Data System (ADS)

Woo, Han Jun; Lee, Jun-Ho; Kang, Jeongwon; Choi, Jae Ung

2017-04-01

Most of the major Korean estuaries, under high pressure from development, have dams with environmental problems, including restricted water circulation, low water quality, decreased biodiversity and wetland destruction. The Nakdong estuary on the southeastern coast of Korean Peninsula is an enclosed type with two large estuarine dams that were constructed in 1934 and between 1983 and 1987. The construction of dams has led to geomorphologic evolution of the barrier islands within Nakdong estuary. The estuary has been characterized as barrier-lagoon system with various subenvironments and microtidal with a 1.5 m tidal range. The sedimentary analyses and monitoring short-term sedimentation rates were investigated to understand characteristics of depositional environments in barrier-lagoon system of the Nakdong River Estuary. The surface sediments in the system were classified into three sedimentary facies in summer 2015. Generally, sand sediment was dominated in the seaward side of barrier islands and muddy sand sediment was dominated on the lagoon. Sandy mud and mud sediments were distributed in the tidal flat near Noksan industrial district and channels near dams. Fourteen a priori subenvironments were distinguished based on differences in landscape characterization (sediment texture, salinity, total organic carbon, pH and C/N ratios). The dendrogram resulting from cluster analysis of environmental variables from 14 a priori subenvironments could be clustered into 4 groups that were characterized by different sediment texture and hydrodynamic energy. The short-term sedimentation rates were obtained seasonally from three lines by burying a plate at sub-bottom depth from May 2015 to May 2016. The deposition was dominated on the tidal flat between mainland and Jinudo (JW- Line) and Sinjado (SJ-Line) with the net deposition rate of 10.09 mm/year and 12.38 mm/year, respectively. The erosion was dominated on the tidal flats at Eulsukdo (ES-Line) on the east side of the system with an annual erosion rate of -13.15 mm/year. Two 12.5-hours anchoring surveys at inlets were revealed that net suspended sediments were transported to the open sea during a tidal cycle in summer 2015 and 2016. The sedimentary processes of the anthropogenically altered barrier-lagoon system in Nakdong estuary showed that sediments transported into the lagoon through inlets during flood condition and moved to westward and deposited sediments on the tidal flat and channels near dams in low energy environments. In the east side of the system, sediments flowed out the sea with discharge from Nakdong Dam during ebb condition. These data will provide an important baseline for future assessments of environmental quality on dam open.

7. View showing placement of timber deck placement on chord ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. View showing placement of timber deck placement on chord and built up construction of top chord and continuous construction through top panel points, eye bar construction on bottom chord - Bridge No. 2.4, Spanning Boiling Fork Creek at Railroad Milepost JC-2.4, Decherd, Franklin County, TN

Construction of membrane-bound artificial cells using microfluidics: a new frontier in bottom-up synthetic biology.

PubMed

Elani, Yuval

2016-06-15

The quest to construct artificial cells from the bottom-up using simple building blocks has received much attention over recent decades and is one of the grand challenges in synthetic biology. Cell mimics that are encapsulated by lipid membranes are a particularly powerful class of artificial cells due to their biocompatibility and the ability to reconstitute biological machinery within them. One of the key obstacles in the field centres on the following: how can membrane-based artificial cells be generated in a controlled way and in high-throughput? In particular, how can they be constructed to have precisely defined parameters including size, biomolecular composition and spatial organization? Microfluidic generation strategies have proved instrumental in addressing these questions. This article will outline some of the major principles underpinning membrane-based artificial cells and their construction using microfluidics, and will detail some recent landmarks that have been achieved. © 2016 The Author(s).

Doped bottom-contact organic field-effect transistors

NASA Astrophysics Data System (ADS)

Liu, Shiyi; Billig, Paul; Al-Shadeedi, Akram; Kaphle, Vikash; Lüssem, Björn

2018-07-01

The influence of doping on doped bottom-gate bottom-contact organic field-effect transistors (OFETs) is discussed. It is shown that the inclusion of a doped layer at the dielectric/organic semiconductor layer leads to a significant reduction in the contact resistances and a fine control of the threshold voltage. Through varying the thickness of the doped layer, a linear shift of threshold voltage V T from ‑3.1 to ‑0.22 V is observed for increasing thickness of doped layer. Meanwhile, the contact resistance at the source and drain electrode is reduced from 138.8 MΩ at V GS = ‑10 V for 3 nm to 0.3 MΩ for 7 nm thick doped layers. Furthermore, an increase of charge mobility is observed for increasing thickness of doped layer. Overall, it is shown that doping can minimize injection barriers in bottom-contact OFETs with channel lengths in the micro-meter regime, which has the potential to increase the performance of this technology further.

Nuclear reactor construction with bottom supported reactor vessel

DOEpatents

Sharbaugh, John E.

1987-01-01

An improved liquid metal nuclear reactor construction has a reactor core and a generally cylindrical reactor vessel for holding a large pool of low pressure liquid metal coolant and housing the core within the pool. The reactor vessel has an open top end, a closed flat bottom end wall and a continuous cylindrical closed side wall interconnecting the top end and bottom end wall. The reactor also has a generally cylindrical concrete containment structure surrounding the reactor vessel and being formed by a cylindrical side wall spaced outwardly from the reactor vessel side wall and a flat base mat spaced below the reactor vessel bottom end wall. A central support pedestal is anchored to the containment structure base mat and extends upwardly therefrom to the reactor vessel and upwardly therefrom to the reactor core so as to support the bottom end wall of the reactor vessel and the lower end of the reactor core in spaced apart relationship above the containment structure base mat. Also, an annular reinforced support structure is disposed in the reactor vessel on the bottom end wall thereof and extends about the lower end of the core so as to support the periphery thereof. In addition, an annular support ring having a plurality of inward radially extending linear members is disposed between the containment structure base mat and the bottom end of the reactor vessel wall and is connected to and supports the reactor vessel at its bottom end on the containment structure base mat so as to allow the reactor vessel to expand radially but substantially prevent any lateral motions that might be imposed by the occurrence of a seismic event. The reactor construction also includes a bed of insulating material in sand-like granular form, preferably being high density magnesium oxide particles, disposed between the containment structure base mat and the bottom end wall of the reactor vessel and uniformly supporting the reactor vessel at its bottom end wall on the containment structure base mat so as to insulate the reactor vessel bottom end wall from the containment structure base mat and allow the reactor vessel bottom end wall to freely expand as it heats up while providing continuous support thereof. Further, a deck is supported upon the side wall of the containment structure above the top open end of the reactor vessel, and a plurality of serially connected extendible and retractable annular bellows extend between the deck and the top open end of the reactor vessel and flexibly and sealably interconnect the reactor vessel at its top end to the deck. An annular guide ring is disposed on the containment structure and extends between its side wall and the top open end of the reactor vessel for providing lateral support of the reactor vessel top open end by limiting imposition of lateral loads on the annular bellows by the occurrence of a lateral seismic event.

A single-layer permeation barrier for organic light-emitting displays

NASA Astrophysics Data System (ADS)

Mandlik, Prashant; Gartside, Jonathan; Han, Lin; Cheng, I.-Chun; Wagner, Sigurd; Silvernail, Jeff A.; Ma, Rui-Qing; Hack, Michael; Brown, Julie J.

2008-03-01

Films of a hybrid material with part-SiO2 part-silicone character are deposited as environmental barriers on bottom-emitting and on transparent organic light-emitting diodes. Devices coated with this barrier have lifetimes of up to ˜7500h when stored at 65°C and 85% relative humidity, by far exceeding the industrial requirement of 1000h. The intensity of the Si-O-Si absorption at the wavenumber of 1075cm-1, the wetting angle by water, and the indentation hardness support the interpretation of a homogeneous material with the properties of a SiO2-silicone hybrid. The films remain intact over 58600cycles of bending to ˜0.2% tensile strain.

Evaluation of Durisol Sound Wall

DOT National Transportation Integrated Search

2000-08-01

The purpose of this final report is to evaluate the durability of Durisol noise barriers constructed in Lehigh County, Lancaster County, and Delaware County. The noise barriers constructed in each of the three counties were manufactured by one of thr...

Traffic noise analysis protocol : for new highway construction, reconstruction and retrofit barrier projects.

DOT National Transportation Integrated Search

2006-08-01

The purpose of this Traffic Noise Analysis Protocol for New Highway : Construction, Reconstruction, and Retrofit Barrier Projects (Protocol) is : to present California Department of Transportation (Caltrans) policies and : procedures for applying 23 ...

Marine methane cycle simulations for the period of early global warming

NASA Astrophysics Data System (ADS)

Elliott, Scott; Maltrud, Mathew; Reagan, Matthew; Moridis, George; Cameron-Smith, Philip

2011-03-01

Geochemical environments, fates, and effects are modeled for methane released into seawater by the decomposition of climate-sensitive clathrates. A contemporary global background cycle is first constructed, within the framework of the Parallel Ocean Program. Input from organics in the upper thermocline is related to oxygen levels, and microbial consumption is parameterized from available rate measurements. Seepage into bottom layers is then superimposed, representing typical seabed fluid flow. The resulting CH4 distribution is validated against surface saturation ratios, vertical sections, and slope plume studies. Injections of clathrate-derived methane are explored by distributing a small number of point sources around the Arctic continental shelf, where stocks are extensive and susceptible to instability during the first few decades of global warming. Isolated bottom cells are assigned dissolved gas fluxes from porous-media simulation. Given the present bulk removal pattern, methane does not penetrate far from emission sites. Accumulated effects, however, spread to the regional scale following the modeled current system. Both hypoxification and acidification are documented. Sensitivity studies illustrate a potential for material restrictions to broaden the perturbations, since methanotrophic consumers require nutrients and trace metals. When such factors are considered, methane buildup within the Arctic basin is enhanced. However, freshened polar surface waters act as a barrier to atmospheric transfer, diverting products into the deep return flow. Uncertainties in the logic and calculations are enumerated including those inherent in high-latitude clathrate abundance, buoyant effluent rise through the column, representation of the general circulation, and bacterial growth kinetics.

Construction of self-cloning bottom-fermenting yeast with low vicinal diketone production by the homo-integration of ILV5.

PubMed

Kusunoki, K; Ogata, T

2012-10-01

The vicinal diketones (VDK), such as diacetyl and 2,3-pentandione, impart an unpleasant butter-like flavour to beer. Typically, these are required to be reduced below the flavour thresholds during the maturation (lagering) stages of the brewing process. To shorten beer maturation time, we constructed a self-cloning, bottom-fermenting yeast with low VDK production by integrating ILV5, a gene encoding a protein that metabolizes α-acetolactate and α-aceto-α-hydroxybutyrate (precursors of VDK). A DNA fragment containing Saccharomyces cerevisiae-type ILV5 was inserted upstream of S. cerevisiae-type ILV2 in bottom-fermenting yeast to construct self-cloning strains with an increased copy number of ILV5. Via transformation, ILV2 was replaced with the sulfometuron methyl (SM) resistance gene SMR1B, which differs by a single nucleotide, to create SM-resistant transformants. The wort fermentation test, using the SC-ILV5-homo inserted transformant, confirmed a consecutive reduction in VDK and a shortening period during which VDK was reduced to within the threshold. The concentrations of ethyl acetate, isoamyl acetate, isoamyl alcohol, 1-propanol, isobutyl alcohol and active isoamyl alcohol (flavour components) were not changed when compared with the parent strain. We successfully constructed self-cloning brewer's yeast in which SC-ILV5 was homo-inserted. Using the transformed yeast, the concentration of VDK in fermenting wort was reduced, whereas the concentrations of flavour components were not affected. This genetically stable, low VDK-producing, self-cloning bottom-fermenting yeast would contribute to the shortening of beer maturation time without affecting important flavour components produced by brewer's yeast. 2012 John Wiley & Sons, Ltd

Non-destructive Analysis Reveals Effect of Installation Details on Plywood Siding Performance

Treesearch

Christopher G. Hunt; Gregory T. Schueneman; Steven Lacher; Xiping Wang; R. Sam Williams

2015-01-01

This study evaluated the influence of a variety of construction techniques on the performance of plywood siding and the applied paint, using both ultrasound and conventional visual inspection techniques. The impact of bottom edge contact, flashing vs. caulking board ends, priming the bottom edge, location (Wisconsin vs. Mississippi) and a gap behind the siding to...

Gate-tunable valley-spin filtering in silicene with magnetic barrier

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, X. Q., E-mail: xianqiangzhe@126.com; Meng, H.

2015-05-28

We theoretically study the valley- and spin-resolved scattering through magnetic barrier in a one layer thick silicene, using the mode-matching method for the Dirac equation. We show that the spin-valley filtering effect can be achieved and can also be tuned completely through both a top and bottom gate. Moreover, when reversing the sign of the staggered potential, we find the direction of the valley polarization is switched while the direction of spin polarization is unchanged. These results can provide some meaningful information to design valley valve residing on silicene.

Effect of the superposition of a dielectric barrier discharge onto a premixed gas burner flame

NASA Astrophysics Data System (ADS)

Zaima, Kazunori; Takada, Noriharu; Sasaki, Koichi

2011-10-01

We are investigating combustion control with the help of nonequilibrium plasma. In this work, we examined the effect of dielectric barrier discharge (DBD) on a premixed burner flame with CH4/O2/Ar gas mixture. The premixed burner flame was covered with a quartz tube. A copper electrode was attached on the outside of the quartz tube, and it was connected to a high-voltage power supply. DBD inside the quartz tube was obtained between the copper electrode and the grounded nozzle of the burner which was placed at the bottom of the quartz tube. We clearly observed that the flame length was shortened by superposing DBD onto the bottom part of the flame. The shortened flame length indicates the enhancement of the burning velocity. We measured the optical emission spectra from the bottom region of the flame. As a result, we observed clear line emissions from Ar, which were never observed from the flame without DBD. We evaluated the rotational temperatures of OH and CH radicals by spectral fitting. As a result, the rotational temperature of CH was not changed, and the rotational temperature of OH was decreased by the superposition of DBD. According to these results, it is considered that the enhancement of the burning velocity is not caused by gas heating. New reaction pathways are suggested.

Perceived barriers to effective job performance among nursing assistants in long-term care.

PubMed

Parmelee, Patricia A; Laszlo, Mary C; Taylor, Jo A

2009-10-01

This research explored perceived barriers to job performance among a national sample of nursing assistants (NAs). Specific objectives were (1) to clarify which of the problems identified by previous research are most troublesome for NAs, (2) to develop a reliable quantitative measure of perceived barriers to job performance, and (3) to test construct validity of the measure vis-à-vis work-related psychological empowerment and job satisfaction. Nursing assistants attending the 2006 national conference of the National Association of Health Care Assistants completed a paper-and-pencil survey including 33 barriers to job performance and standardized measures of empowerment and job satisfaction. The barriers were also rated by a small sample of NAs at a single Georgia nursing home. Factor analysis of barriers items yielded a 30-item Nursing Assistants Barriers Scale (NABS) comprising 6 subscales: Teamwork, Exclusion, Respect, Workload, Work Stress, and New NAs. Lack of teamwork and exclusion from communication processes were rated as most problematic by both samples. The 6 NABS subscales were significantly and independently associated with empowerment and satisfaction; different barriers predicted the 2 constructs. This study is a first step toward quantitative assessment of NAs' perceptions of barriers to doing their jobs. Primary limitations are the select sample and use of a job satisfaction measure that may have artificially inflated correlations with the NABS. Nonetheless, results confirm the validity of the new scale as an operationalization of the barriers construct. The concept of barriers to job performance is a unique construct from work empowerment and satisfaction with one's job. Nursing assistants clearly differentiate various barriers, converging on workload and lack of teamwork as most problematic. Further work is needed to substantiate validity and reliability of the NABS, particularly with respect to NAs' actual job performance, intent to stay on the job versus leave, absenteeism, and turnover.

Evaluation of effect of different disposable infection control barriers on light intensity of light-curing unit and microhardness of composite - An in vitro study.

PubMed

Khode, Rajiv Tarachand; Shenoi, Pratima Ramakrishna; Kubde, Rajesh R; Makade, Chetana S; Wadekar, Kanchan D; Khode, Priyanka Tarachand

2017-01-01

This study evaluated effect of infection control barriers on light intensity (LI) of light-curing unit (LCU) and microhardness of composite. Four different disposable barriers ( n = 30) were tested against the control. LI for each barrier was measured with Lux meter. One hundred and fifty Teflon molds were equally divided into five groups of thirty each. Composite was filled in bulk in these molds and cured without and with barrier. Microhardness was evaluated on top and bottom surface of composite specimen with microhardness testing machine and hardness ratio (HR) was derived. One-way analysis of variance, Tukey's honestly significant difference test, and paired t -test using SPSS version 18 software. All barriers had significantly reduced the baseline LI of LCU ( P < 0.0001), but only Cure Elastic Steri-Shield and latex cut glove pieces (LCGP) significantly reduced the microhardness of the composite ( P < 0.05). However, HR determined inadequate curing only with LCGP. Although entire tested barrier significantly reduced the LI; none, except LCGP markedly affected the degree of cure of the composite.

LED structure with enhanced mirror reflectivity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bergmann, Michael; Donofrio, Matthew; Heikman, Sten

2014-04-01

Embodiments of the present invention are generally related to LED chips having improved overall emission by reducing the light-absorbing effects of barrier layers adjacent mirror contacts. In one embodiment, a LED chip comprises one or more LEDs, with each LED having an active region, a first contact under the active region having a highly reflective mirror, and a barrier layer adjacent the mirror. The barrier layer is smaller than the mirror such that it does not extend beyond the periphery of the mirror. In another possible embodiment, an insulator is further provided, with the insulator adjacent the barrier layer andmore » adjacent portions of the mirror not contacted by the active region or by the barrier layer. In yet another embodiment, a second contact is provided on the active region. In a further embodiment, the barrier layer is smaller than the mirror such that the periphery of the mirror is at least 40% free of the barrier layer, and the second contact is below the first contact and accessible from the bottom of the chip.« less

The Bottom Line: An Exercise to Help Students Understand How Social Inequality Is Actively Constructed

ERIC Educational Resources Information Center

Abelev, Melissa; Vincent, M. Bess; Haney, Timothy J.

2008-01-01

One of the important misconceptions in the American view of poverty is that people are poor because they do not work. This article presents an exercise, the "bottom line," which helps dispel students' misconceptions about the working poor. Through extensive primary-data collection and assembling a budget for low-skilled workers, the exercise: (1)…

A road pavement full-scale test track containing stabilized bottom ashes.

PubMed

Toraldo, E; Saponaro, S

2015-01-01

This paper reports the results of a road pavement full-scale test track built by using stabilized bottom ash (SBA) from an Italian municipal solid waste incinerator as the aggregate in granular foundation, cement-bound mixes and asphalt concretes. The investigation focused on both the performance and the environmental compatibility of such mixes, especially with regard to the effects of mixing, laying and compaction. From the road construction point of view, the performance related to the effects of mixing, laying and compaction on constructability was assessed, as well as the volumetric and the mechanical properties. Environmental aspects were investigated by leaching tests. The results suggested that SBA meets the environmental Italian law for the reuse of non-hazardous waste and could be used as road material with the procedures, plants and equipment currently used for road construction.

Automated 3D bioassembly of micro-tissues for biofabrication of hybrid tissue engineered constructs.

PubMed

Mekhileri, N V; Lim, K S; Brown, G C J; Mutreja, I; Schon, B S; Hooper, G J; Woodfield, T B F

2018-01-12

Bottom-up biofabrication approaches combining micro-tissue fabrication techniques with extrusion-based 3D printing of thermoplastic polymer scaffolds are emerging strategies in tissue engineering. These biofabrication strategies support native self-assembly mechanisms observed in developmental stages of tissue or organoid growth as well as promoting cell-cell interactions and cell differentiation capacity. Few technologies have been developed to automate the precise assembly of micro-tissues or tissue modules into structural scaffolds. We describe an automated 3D bioassembly platform capable of fabricating simple hybrid constructs via a two-step bottom-up bioassembly strategy, as well as complex hybrid hierarchical constructs via a multistep bottom-up bioassembly strategy. The bioassembly system consisted of a fluidic-based singularisation and injection module incorporated into a commercial 3D bioprinter. The singularisation module delivers individual micro-tissues to an injection module, for insertion into precise locations within a 3D plotted scaffold. To demonstrate applicability for cartilage tissue engineering, human chondrocytes were isolated and micro-tissues of 1 mm diameter were generated utilising a high throughput 96-well plate format. Micro-tissues were singularised with an efficiency of 96.0 ± 5.1%. There was no significant difference in size, shape or viability of micro-tissues before and after automated singularisation and injection. A layer-by-layer approach or aforementioned bottom-up bioassembly strategy was employed to fabricate a bilayered construct by alternatively 3D plotting a thermoplastic (PEGT/PBT) polymer scaffold and inserting pre-differentiated chondrogenic micro-tissues or cell-laden gelatin-based (GelMA) hydrogel micro-spheres, both formed via high-throughput fabrication techniques. No significant difference in viability between the construct assembled utilising the automated bioassembly system and manually assembled construct was observed. Bioassembly of pre-differentiated micro-tissues as well as chondrocyte-laden hydrogel micro-spheres demonstrated the flexibility of the platform while supporting tissue fusion, long-term cell viability, and deposition of cartilage-specific extracellular matrix proteins. This technology provides an automated and scalable pathway for bioassembly of both simple and complex 3D tissue constructs of clinically relevant shape and size, with demonstrated capability to facilitate direct spatial organisation and hierarchical 3D assembly of micro-tissue modules, ranging from biomaterial free cell pellets to cell-laden hydrogel formulations.

Demonstration of close-coupled barriers for subsurface containment of buried waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dwyer, B.P.

1996-05-01

A close-coupled barrier is produced by first installing a conventional cement grout curtain followed by a thin inner lining of a polymer grout. The resultant barrier is a cement polymer composite that has economic benefits derived from the cement and performance benefits from the durable and resistant polymer layer. Close-coupled barrier technology is applicable for final, interim, or emergency containment of subsurface waste forms. Consequently, when considering the diversity of technology application, the construction emplacement and material technology maturity, general site operational requirements, and regulatory compliance incentives, the close-coupled barrier system provides an alternative for any hazardous or mixed wastemore » remediation plan. This paper discusses the installation of a close-coupled barrier and the subsequent integrity verification. The demonstration was installed at a benign site at the Hanford Geotechnical Test Facility, 400 Area, Hanford, Washington. The composite barrier was emplaced beneath a 7,500 liter tank. The tank was chosen to simulate a typical DOE Complex waste form. The stresses induced on the waste form were evaluated during barrier construction. The barrier was constructed using conventional jet grouting techniques. Drilling was completed at a 45{degree} angle to the ground, forming a conical shaped barrier with the waste form inside the cone. Two overlapping rows of cylindrical cement columns were grouted in a honeycomb fashion to form the secondary backdrop barrier layer. The primary barrier, a high molecular weight polymer manufactured by 3M Company, was then installed providing a relatively thin inner liner for the secondary barrier. The primary barrier was emplaced by panel jet grouting with a dual wall drill stem, two phase jet grouting system.« less

State of offsite construction in India-Drivers and barriers

NASA Astrophysics Data System (ADS)

Arif, M.; Bendi, D.; Sawhney, A.; Iyer, K. C.

2012-05-01

The rapid growth of the construction industry in India has influenced key players in the industry to adopt alternative technologies addressing time, cost and quality. The rising demand in housing, infrastructure and other facilities have further highlighted the need for the construction industry to look at adopting alternate building technologies. Offsite construction has evolved as a panacea to dealing with the under-supply and poor quality in the current age construction industry. Several offsite techniques have been adopted by the construction sector. Although, different forms of offsite techniques have been around for a while but their uptake has been low in the Indian context. This paper presents the perceptions about offsite construction in India and highlights some of the barriers and drivers facing the Indian construction industry. The data was gathered through a survey of 17 high level managers from some of the largest stakeholder organizations of the construction sector in India. The influence of time and cost has been highlighted as a major factor fuelling the adoption of offsite construction. However, the influence of current planning systems and the need for a paradigm shift are some of the prominent barriers towards the adoption of offsite techniques.

Theoretical domains framework to assess barriers to change for planning health care quality interventions: a systematic literature review.

PubMed

Mosavianpour, Mirkaber; Sarmast, Hamideh Helen; Kissoon, Niranjan; Collet, Jean-Paul

2016-01-01

Theoretical domains framework (TDF) provides an integrative model for assessing barriers to behavioral changes in order to suggest interventions for improvement in behavior and ultimately outcomes. However, there are other tools that are used to assess barriers. The objective of this study is to determine the degree of concordance between domains and constructs identified in two versions of the TDF including original (2005) and refined version (2012) and independent studies of other tools. We searched six databases for articles that studied barriers to health-related behavior changes of health care professionals or the general public. We reviewed quantitative papers published in English which included their questionnaires in the article. A table including the TDF domains of both original and refined versions and related constructs was developed to serve as a reference to describe the barriers assessed in the independent studies; descriptive statistics were used to express the results. Out of 552 papers retrieved, 50 were eligible to review. The barrier domains explored in these articles belonged to two to eleven domains of the refined TDF. Eighteen articles (36%) used constructs outside of the refined version. The spectrum of barrier constructs of the original TDF was broader and could meet the domains studied in 48 studies (96%). Barriers in domains of "environmental context and resources", "beliefs about consequences", and "social influences" were the most frequently explored in 42 (84%), 37 (74%), and 33 (66%) of the 50 articles, respectively. Both refined and original TDFs cataloged barriers measured by the other studies that did not use TDF as their framework. However, the original version of TDF explored a broader spectrum of barriers than the refined version. From this perspective, the original version of the TDF seems to be a more comprehensive tool for assessing barriers in practice.

Method and apparatus for suppressing waves in a borehole

DOEpatents

West, Phillip B.

2005-10-04

Methods and apparatus for suppression of wave energy within a fluid-filled borehole using a low pressure acoustic barrier. In one embodiment, a flexible diaphragm type device is configured as an open bottomed tubular structure for disposition in a borehole to be filled with a gas to create a barrier to wave energy, including tube waves. In another embodiment, an expandable umbrella type device is used to define a chamber in which a gas is disposed. In yet another embodiment, a reverse acting bladder type device is suspended in the borehole. Due to its reverse acting properties, the bladder expands when internal pressure is reduced, and the reverse acting bladder device extends across the borehole to provide a low pressure wave energy barrier.

Long-Term Drainage from the Riprap Side Slope of a Surface Barrier

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Zhuanfang

Surface barriers designed to isolate underground nuclear waste in place are expected to function for at least 1000 years. To achieve this long design life, such barriers need to be protected with side slopes against wind- and water-induced erosion and damage by natural or human activities. However, the side slopes are usually constructed with materials coarser than the barrier. Their hydrological characteristics must be understood so that any drainage from them is considered in the barrier design and will not compromise the barrier function. The Prototype Hanford Barrier, an evapotranspiration-capillary (ETC) barrier, was constructed in 1994 at the Hanford Sitemore » in southeastern Washington state, with a gravel side slope and a riprap side slope. The soil water content in the gravel side slope and drainage from both side slopes have been monitored since the completion of construction. The monitoring results show that under natural precipitation the annual drainage rates from the two types of side slopes were very similar and about 5 times the typical recharge from local soil with natural vegetation and 40 times the barrier design criterion. The higher recharge from the side slopes results in some of the drainage migrating laterally to the region beneath the ETC barrier. This edge effect of the enhanced drainage was evaluated for a period of 1000 years by numerical simulation. The edge effect was quantified by the amount of water across the barrier edges and the affecting distance of the barrier edges. These results indicate that design features can be adjusted to reduce the edge effect when necessary.« less

Properties of GaP Schottky barrier diodes at elevated temperatures.

NASA Technical Reports Server (NTRS)

Nannichi, Y.; Pearson, G. L.

1969-01-01

Gallium phosphide Schottky barrier diodes, discussing construction and metals used, barrier height relationships to impurity concentration and temperature, rectifying characteristics and internal quantum efficiency

Research notes : time to clean up those barrier markers.

DOT National Transportation Integrated Search

1999-07-01

In February 1997, ODOT Construction installed seven types of barrier markers to investigate short-term performance. The barrier markers are typically installed on the top of concrete barriers or other delineators to visually enhance the alignment. Th...

Development and testing of synthetic RIPRAP constructed from coal combustion products.

DOT National Transportation Integrated Search

2013-11-01

Even with an increase in the amount of CCPs used in concrete construction, soil stabilization, and other applications, the coal power : industry must dispose of a significant amount of fly ash and bottom ash. One potential avenue for the material is ...

Development and testing of synthetic riprap constructed from coal combustion products (CCPs).

DOT National Transportation Integrated Search

2014-07-01

Even with an increase in the amount of coal combustion products (CCPs) used in concrete con-struction, soil stabilization, and other : applications, the coal power industry must dispose of a sig-nificant amount of fly ash and bottom ash. One potentia...

In vitro biodegradation testing of Mg-alloy EZK400 and manufacturing of implant prototypes using PM (powder metallurgy) methods.

PubMed

Wolff, M; Luczak, M; Schaper, J G; Wiese, B; Dahms, M; Ebel, T; Willumeit-Römer, R; Klassen, T

2018-09-01

The study is focussing towards Metal Injection Moulding (MIM) of Mg-alloys for biomedical implant applications. Especially the influence of the sintering processing necessary for the consolidation of the finished part is in focus of this study. In doing so, the chosen high strength EZK400 Mg-alloy powder material was sintered using different sintering support bottom plate materials to evaluate the possibility of iron impurity pick up during sintering. It can be shown that iron pick up took place from the steel bottom plate into the specimen. Despite the fact that a separating boron nitrite (BN) barrier layer was used and the Mg-Fe phase diagram is not predicting any significant solubility to each other. As a result of this study a new bottom plate material not harming the sintering and the biodegradation performance of the as sintered material, namely a carbon plate material, was found.

Method and apparatus for spatially uniform electropolishing and electrolytic etching

DOEpatents

Mayer, Steven T.; Contolini, Robert J.; Bernhardt, Anthony F.

1992-01-01

In an electropolishing or electrolytic etching apparatus the anode is separated from the cathode to prevent bubble transport to the anode and to produce a uniform current distribution at the anode by means of a solid nonconducting anode-cathode barrier. The anode extends into the top of the barrier and the cathode is outside the barrier. A virtual cathode hole formed in the bottom of the barrier below the level of the cathode permits current flow while preventing bubble transport. The anode is rotatable and oriented horizontally facing down. An extended anode is formed by mounting the workpiece in a holder which extends the electropolishing or etching area beyond the edge of the workpiece to reduce edge effects at the workpiece. A reference electrode controls cell voltage. Endpoint detection and current shut-off stop polishing. Spatially uniform polishing or etching can be rapidly performed.

Method and apparatus for spatially uniform electropolishing and electrolytic etching

DOEpatents

Mayer, S.T.; Contolini, R.J.; Bernhardt, A.F.

1992-03-17

In an electropolishing or electrolytic etching apparatus the anode is separated from the cathode to prevent bubble transport to the anode and to produce a uniform current distribution at the anode by means of a solid nonconducting anode-cathode barrier. The anode extends into the top of the barrier and the cathode is outside the barrier. A virtual cathode hole formed in the bottom of the barrier below the level of the cathode permits current flow while preventing bubble transport. The anode is rotatable and oriented horizontally facing down. An extended anode is formed by mounting the workpiece in a holder which extends the electropolishing or etching area beyond the edge of the workpiece to reduce edge effects at the workpiece. A reference electrode controls cell voltage. Endpoint detection and current shut-off stop polishing. Spatially uniform polishing or etching can be rapidly performed. 6 figs.

It serves you right. Hassle-free health care builds loyalty, volume--and the bottom line.

PubMed

Larkin, H

Zero barriers to care, zero waiting times: Tough as those targets sound, today's stars of customer service are scoring direct hits. "It's not a change in the services that are delivered," says one patient satisfaction pro. "It's a change in the way they're being delivered."

Show Us How: A School-Wide Programme for Reluctant Readers.

ERIC Educational Resources Information Center

Maguiness, Colleen

Westerns Springs College in Auckland, New Zealand is an inner city coeducational secondary school of 670 multicultural and diverse students. Achievement test results in reading comprehension and vocabulary grouped students at the top and bottom of the scale. Reading was identified as a significant barrier to learning and in 1997 staff agreed to…

Short-channel field-effect transistors with 9-atom and 13-atom wide graphene nanoribbons

DOE Office of Scientific and Technical Information (OSTI.GOV)

Llinas, Juan Pablo; Fairbrother, Andrew; Borin Barin, Gabriela

Bottom-up synthesized graphene nanoribbons and graphene nanoribbon heterostructures have promising electronic properties for high-performance field-effect transistors and ultra-low power devices such as tunneling field-effect transistors. However, the short length and wide band gap of these graphene nanoribbons have prevented the fabrication of devices with the desired performance and switching behavior. Here, by fabricating short channel (L ch ~ 20 nm) devices with a thin, high-κ gate dielectric and a 9-atom wide (0.95 nm) armchair graphene nanoribbon as the channel material, we demonstrate field-effect transistors with high on-current (I on > 1 μA at V d = -1 V) and highmore » I on /I off ~ 10 5 at room temperature. We find that the performance of these devices is limited by tunneling through the Schottky barrier at the contacts and we observe an increase in the transparency of the barrier by increasing the gate field near the contacts. Our results thus demonstrate successful fabrication of high-performance short-channel field-effect transistors with bottom-up synthesized armchair graphene nanoribbons.« less

Short-channel field-effect transistors with 9-atom and 13-atom wide graphene nanoribbons

DOE PAGES

Llinas, Juan Pablo; Fairbrother, Andrew; Borin Barin, Gabriela; ...

2017-09-21

Bottom-up synthesized graphene nanoribbons and graphene nanoribbon heterostructures have promising electronic properties for high-performance field-effect transistors and ultra-low power devices such as tunneling field-effect transistors. However, the short length and wide band gap of these graphene nanoribbons have prevented the fabrication of devices with the desired performance and switching behavior. Here, by fabricating short channel (L ch ~ 20 nm) devices with a thin, high-κ gate dielectric and a 9-atom wide (0.95 nm) armchair graphene nanoribbon as the channel material, we demonstrate field-effect transistors with high on-current (I on > 1 μA at V d = -1 V) and highmore » I on /I off ~ 10 5 at room temperature. We find that the performance of these devices is limited by tunneling through the Schottky barrier at the contacts and we observe an increase in the transparency of the barrier by increasing the gate field near the contacts. Our results thus demonstrate successful fabrication of high-performance short-channel field-effect transistors with bottom-up synthesized armchair graphene nanoribbons.« less

33 CFR 148.5 - How are terms used in this subchapter defined?

Code of Federal Regulations, 2011 CFR

2011-07-01

... and calculations for construction of deepwater ports, conducting inspections, witnessing tests, and..., or naturalization; (2) Any State, State agency, or group of States; or (3) Any corporation... cofferdam or double bottom tank; or (2) Is not designed for continuous occupancy by personnel. Construction...

Recovery of cesium

DOEpatents

Izatt, Reed M.; Christensen, James J.; Hawkins, Richard T.

1984-01-01

A process of recovering cesium ions from mixtures of ions containing them and other ions, e.g., a solution of nuclear waste materials, which comprises establishing a separate source phase containing such a mixture of ions, establishing a separate recipient phase, establishing a liquid membrane phase in interfacial contact with said source and recipient phases, said membrane phase containing a ligand, preferably a selected calixarene as depicted in the drawing, maintaining said interfacial contact for a period of time long enough to transport by said ligand a substantial portion of the cesium ion from the source phase to the recipient phase, and recovering the cesium ion from the recipient phase. The separation of the source and recipient phases may be by the membrane phase only, e.g., where these aqueous phases are emulsified as dispersed phases in a continuous membrane phase, or may include a physical barrier as well, e.g., an open-top outer container with an inner open-ended container of smaller cross-section mounted in the outer container with its open bottom end spaced from and above the closed bottom of the outer container so that the membrane phase may fill the outer container to a level above the bottom of the inner container and have floating on its upper surface a source phase and a recipient phase separated by the wall of the inner container as a physical barrier. A preferred solvent for the ligand is a mixture of methylene chloride and carbon tetrachloride.

Short-channel field-effect transistors with 9-atom and 13-atom wide graphene nanoribbons.

PubMed

Llinas, Juan Pablo; Fairbrother, Andrew; Borin Barin, Gabriela; Shi, Wu; Lee, Kyunghoon; Wu, Shuang; Yong Choi, Byung; Braganza, Rohit; Lear, Jordan; Kau, Nicholas; Choi, Wonwoo; Chen, Chen; Pedramrazi, Zahra; Dumslaff, Tim; Narita, Akimitsu; Feng, Xinliang; Müllen, Klaus; Fischer, Felix; Zettl, Alex; Ruffieux, Pascal; Yablonovitch, Eli; Crommie, Michael; Fasel, Roman; Bokor, Jeffrey

2017-09-21

Bottom-up synthesized graphene nanoribbons and graphene nanoribbon heterostructures have promising electronic properties for high-performance field-effect transistors and ultra-low power devices such as tunneling field-effect transistors. However, the short length and wide band gap of these graphene nanoribbons have prevented the fabrication of devices with the desired performance and switching behavior. Here, by fabricating short channel (L ch  ~ 20 nm) devices with a thin, high-κ gate dielectric and a 9-atom wide (0.95 nm) armchair graphene nanoribbon as the channel material, we demonstrate field-effect transistors with high on-current (I on  > 1 μA at V d  = -1 V) and high I on /I off  ~ 10 5 at room temperature. We find that the performance of these devices is limited by tunneling through the Schottky barrier at the contacts and we observe an increase in the transparency of the barrier by increasing the gate field near the contacts. Our results thus demonstrate successful fabrication of high-performance short-channel field-effect transistors with bottom-up synthesized armchair graphene nanoribbons.Graphene nanoribbons show promise for high-performance field-effect transistors, however they often suffer from short lengths and wide band gaps. Here, the authors use a bottom-up synthesis approach to fabricate 9- and 13-atom wide ribbons, enabling short-channel transistors with 10 5 on-off current ratio.

Life cycle based risk assessment of recycled materials in roadway construction.

PubMed

Carpenter, A C; Gardner, K H; Fopiano, J; Benson, C H; Edil, T B

2007-01-01

This paper uses a life-cycle assessment (LCA) framework to characterize comparative environmental impacts from the use of virgin aggregate and recycled materials in roadway construction. To evaluate site-specific human toxicity potential (HTP) in a more robust manner, metals release data from a demonstration site were combined with an unsaturated contaminant transport model to predict long-term impacts to groundwater. The LCA determined that there were reduced energy and water consumption, air emissions, Pb, Hg and hazardous waste generation and non-cancer HTP when bottom ash was used in lieu of virgin crushed rock. Conversely, using bottom ash instead of virgin crushed rock increased the cancer HTP risk due to potential leachate generation by the bottom ash. At this scale of analysis, the trade-offs are clearly between the cancer HTP (higher for bottom ash) and all of the other impacts listed above (lower for bottom ash). The site-specific analysis predicted that the contaminants (Cd, Cr, Se and Ag for this study) transported from the bottom ash to the groundwater resulted in very low unsaturated zone contaminant concentrations over a 200 year period due to retardation in the vadose zone. The level of contaminants predicted to reach the groundwater after 200 years was significantly less than groundwater maximum contaminant levels (MCL) set by the US Environmental Protection Agency for drinking water. Results of the site-specific contaminant release estimates vary depending on numerous site and material specific factors. However, the combination of the LCA and the site specific analysis can provide an appropriate context for decision making. Trade-offs are inherent in making decisions about recycled versus virgin material use, and regulatory frameworks should recognize and explicitly acknowledge these trade-offs in decision processes.

Recognition and Construction of Top, Bottom, and Versatile Orientations in Gay/Bisexual Men.

PubMed

Moskowitz, David A; Roloff, Michael E

2017-01-01

Research on gay and bisexual men's sexual position self-label (i.e., being a top, bottom, or versatile during anal sex) has revealed only independent snapshots of its development by focusing primarily on the influence of penis size. Moreover, the basic chronology of development of the sexual position self-label has barely been addressed. In response, we implemented a survey of 282 gay and bisexual men that measured demographics (including height and penis size), age of sexual recognitions, sexual position self-label, and attitudinal constructs suggested by previous literature as important (e.g., pleasure, control, anxieties, and gender typicality). Results suggested that men's sexual position self-label was learned over a 15-year timespan. Ages of first same-sex genital manipulation and first anal sex experiences were related to age at first self-labeling. With respect to predictors of labels, a multivariate path model was created. The model did not support the direct importance of penis size, but identified indirect paths that linked penis size to top/bottom identification (e.g., smaller penis sizes leading to topping-anxieties and thus, a bottom label). Finding bottoming to be pleasurable and the importance of sexual control dynamics were the only two direct predictors. The path model substantiated the reliance both bottoms and tops show towards seeking (or not seeking among tops) gender typical, sexually dominant partners. It also supported previous evidence regarding race; specifically, while race may activate differences in sexual behavioral dynamics, it is not a great predictor of the sexual position self-label. This study shows that sexual position self-labeling has enormous complexity and cannot be reduced down to penis size.

Evaluation of effect of different disposable infection control barriers on light intensity of light-curing unit and microhardness of composite - An in vitro study

PubMed Central

Khode, Rajiv Tarachand; Shenoi, Pratima Ramakrishna; Kubde, Rajesh R.; Makade, Chetana S.; Wadekar, Kanchan D.; Khode, Priyanka Tarachand

2017-01-01

Aims: This study evaluated effect of infection control barriers on light intensity (LI) of light-curing unit (LCU) and microhardness of composite. Materials and Methods: Four different disposable barriers (n = 30) were tested against the control. LI for each barrier was measured with Lux meter. One hundred and fifty Teflon molds were equally divided into five groups of thirty each. Composite was filled in bulk in these molds and cured without and with barrier. Microhardness was evaluated on top and bottom surface of composite specimen with microhardness testing machine and hardness ratio (HR) was derived. Statistical Analysis Used: One-way analysis of variance, Tukey's honestly significant difference test, and paired t-test using SPSS version 18 software. Results: All barriers had significantly reduced the baseline LI of LCU (P < 0.0001), but only Cure Elastic Steri-Shield and latex cut glove pieces (LCGP) significantly reduced the microhardness of the composite (P < 0.05). However, HR determined inadequate curing only with LCGP. Conclusions: Although entire tested barrier significantly reduced the LI; none, except LCGP markedly affected the degree of cure of the composite. PMID:29279622

Investigation of microstructure and properties of ultrathin graded ZrNx self-assembled diffusion barrier in deep nano-vias prepared by plasma ion immersion implantation

NASA Astrophysics Data System (ADS)

Zou, Jianxiong; Liu, Bo; Lin, Liwei; Lu, Yuanfu; Dong, Yuming; Jiao, Guohua; Ma, Fei; Li, Qiran

2018-01-01

Ultrathin graded ZrNx self-assembled diffusion barriers with controllable stoichiometry was prepared in Cu/p-SiOC:H interfaces by plasma immersion ion implantation (PIII) with dynamic regulation of implantation fluence. The fundamental relationship between the implantation fluence of N+ and the stoichiometry and thereby the electrical properties of the ZrNx barrier was established. The optimized fluence of a graded ZrN thin film with gradually decreased Zr valence was obtained with the best electrical performance as well. The Cu/p-SiOC:H integration is thermally stable up to 500 °C due to the synergistic effect of Cu3Ge and ZrNx layers. Accordingly, the PIII process was verified in a 100-nm-thick Cu dual-damascene interconnect, in which the ZrNx diffusion barrier of 1 nm thick was successfully self-assembled on the sidewall without barrier layer on the via bottom. In this case, the via resistance was reduced by approximately 50% in comparison with Ta/TaN barrier. Considering the results in this study, ultrathin ZrNx conformal diffusion barrier can be adopted in the sub-14 nm technology node.

49 CFR 571.121 - Standard No. 121; Air brake systems.

Code of Federal Regulations, 2013 CFR

2013-10-01

... inches with extendable equipment in the fully retracted position and is equipped with two short track... construction that accommodates harvest containers, a maximum length of 28 feet, and an arrangement of air.... Container chassis trailer means a semitrailer of skeleton construction limited to a bottom frame, one or...

49 CFR 571.121 - Standard No. 121; Air brake systems.

Code of Federal Regulations, 2012 CFR

2012-10-01

... inches with extendable equipment in the fully retracted position and is equipped with two short track... construction that accommodates harvest containers, a maximum length of 28 feet, and an arrangement of air.... Container chassis trailer means a semitrailer of skeleton construction limited to a bottom frame, one or...

49 CFR 571.121 - Standard No. 121; Air brake systems.

Code of Federal Regulations, 2014 CFR

2014-10-01

... inches with extendable equipment in the fully retracted position and is equipped with two short track... construction that accommodates harvest containers, a maximum length of 28 feet, and an arrangement of air.... Container chassis trailer means a semitrailer of skeleton construction limited to a bottom frame, one or...

Significant genetic boundaries and spatial dynamics of giant pandas occupying fragmented habitat across southwest China.

PubMed

Zhu, Lifeng; Zhang, Shanning; Gu, Xiaodong; Wei, Fuwen

2011-03-01

Understanding population history and genetic structure are key drivers of ecological research. Here, we studied two highly fragmented and isolated populations (Xiaoxiangling and Daxiangling) of giant pandas (Ailuropoda melanoleuca) at the extreme southwestern edge of their distribution. This area also contains the Dadu River, national road 108 and various human infrastructure and development, providing an ideal region in which we can identify the effects of different barriers on animal movements. We used partial mitochondrial control region (mtDNA) and nine microsatellite loci (nuclear DNA) data derived from 192 faecal and one blood sample collected from the wild. We found 136 genotypes corresponding to 53 unique multilocus genotypes and eight unique control region haplotypes (653 bp). Significant genetic boundaries correlated spatially with the Dadu River (K = 2). We estimate that a major divergence took place between these populations 26,000 years bp, at around the similar time the rock surface of valley bottom formed in Dadu River. The national road has resulted in further recent population differentiation (Pairwise F(S) on mtDNA and nuclear DNA) so that in effect, four smaller sub-populations now exist. Promisingly, we identified two possible first-generation migrants and their migration paths, and recommended the immediate construction of a number of corridors. Fortunately, the Chinese government has accepted our advice and is now planning corridor construction. © 2011 Blackwell Publishing Ltd.

The future cost of electrical energy storage based on experience rates

NASA Astrophysics Data System (ADS)

Schmidt, O.; Hawkes, A.; Gambhir, A.; Staffell, I.

2017-08-01

Electrical energy storage could play a pivotal role in future low-carbon electricity systems, balancing inflexible or intermittent supply with demand. Cost projections are important for understanding this role, but data are scarce and uncertain. Here, we construct experience curves to project future prices for 11 electrical energy storage technologies. We find that, regardless of technology, capital costs are on a trajectory towards US$340 ± 60 kWh-1 for installed stationary systems and US$175 ± 25 kWh-1 for battery packs once 1 TWh of capacity is installed for each technology. Bottom-up assessment of material and production costs indicates this price range is not infeasible. Cumulative investments of US$175-510 billion would be needed for any technology to reach 1 TWh deployment, which could be achieved by 2027-2040 based on market growth projections. Finally, we explore how the derived rates of future cost reduction influence when storage becomes economically competitive in transport and residential applications. Thus, our experience-curve data set removes a barrier for further study by industry, policymakers and academics.

Facilitators & Barriers to the Adoption of Ergonomic Solutions in Construction

PubMed Central

Dale, Ann Marie; Jaegers, Lisa; Welch, Laura; Barnidge, Ellen; Weaver, Nancy; Evanoff, Bradley A.

2017-01-01

Background Rates of musculoskeletal disorders in construction remain high. Few studies have described barriers and facilitators to the use of available ergonomic solutions. This paper describes these barriers and facilitators and their relationship to the level of adoption. Methods Three analysts rated 16 proposed ergonomic solutions from a participatory ergonomics study and assessed the level of adoption, six adoption characteristics, and identified the category of adoption from a theoretical model. Results Twelve solutions were always or intermittently used and were rated positively for characteristics of relative advantage, compatibility with existing work processes, and trialability. Locus of control (worker vs. contractor) was not related to adoption. Simple solutions faced fewer barriers to adoption than those rated as complex. Conclusions Specific adoption characteristics can help predict the use of new ergonomic solutions in construction. Adoption of complex solutions must involve multiple stakeholders, more time, and shifts in culture or work systems. PMID:28195660

TRICHLOROETHYLENE REMOVAL FROM GROUNDWATER IN FLOW-THROUGH COLUMNS SIMULATING A PERMEABLE REACTIVE BARRIER CONSTRUCTED WITH PLANT MULCH

EPA Science Inventory

Ground water contaminated with TCE is commonly treated with a passive reactive barrier (PRB) constructed with zero-valence iron. The cost of iron as the reactive matrix has driven a search for less costly alternatives, and composted plant mulch has been used as an alternative re...

Disseminating effective clinician communication techniques: Engaging clinicians to want to learn how to engage patients.

PubMed

Pollak, Kathryn I; Back, Anthony L; Tulsky, James A

2017-10-01

Patient-clinician communication that promotes patient engagement enhances health care quality. Yet, disseminating effective communication interventions to practicing clinicians remains challenging. Current methods do not have large and sustainable effects. In this paper, we argue that both top-down approaches (mandated by institutions) should be coupled with bottom-up approaches that address clinician motivation, confidence, and barriers. We need to engage clinicians in the same way we ask them to engage patients - strategically and with empathy. We discuss potentially innovative strategies to integrate top-down and bottom-up approaches in ways that fit clinicians' busy schedules and can inform policy. Copyright © 2017. Published by Elsevier B.V.

[Simulation on contamination forecast and control of groundwater in a certain hazardous waste landfill].

PubMed

Ma, Zhi-Fei; An, Da; Jiang, Yong-Hai; Xi, Bei-Dou; Li, Ding-Long; Zhang, Jin-Bao; Yang, Yu

2012-01-01

On the basis of site investigation and data collection of a certain hazardous waste landfill, the groundwater flow and solute transport coupled models were established by applying Visual Modflow software, which was used to conduct a numerical simulation that forecast the transport process of Cr6+ in groundwater and the effects of three control measures (ground-harden, leakage-proof barriers and drainage ditches) of contaminants transport after leachate leakage happened in impermeable layer of the landfill. The results show that the contamination plume of Cr6+ transports with groundwater flow direction, the contamination rang would reach the pool's boundary in 10 years, and the distance of contamination transport is 1 450 m. But the diffusion range of contamination plume would not be obviously expanded between 10 and 20 years. While the ground is hardened, the contamination plume would not reach the pool's boundary in 20 years. When the leakage-proof barrier is set in the bottom of water table aquifer, the concentration of Cr6+ is higher than that the leakage-proof barrier is unset, but the result is just opposite when setting the leakage-proof barrier in the bottom of underlying aquifer. The range of contamination plume is effectively controlled by setting drainage ditches that water discharge is 2 642 m3 x d(-1), which makes the monitoring wells would not be contaminated in 20 years. Moreover, combining the ground-harden with drainage ditches can get the best effect in controlling contaminants diffusion, and meanwhile, the drainage ditches' daily discharge is reduced to 1 878 m3 x d(-1). Therefore, it is suggested that the control measure combining the ground-harden with drainage ditches should apply to prevent contamination diffusion in groundwater when leachate leakage have happened in impermeable layer of the landfill.

Effects of electrodes on the properties of sol-gel PZT based capacitors in FeRAM

NASA Astrophysics Data System (ADS)

Zhang, Ming-Ming; Jia, Ze; Ren, Tian-Ling

2009-05-01

The effects of electrodes on the properties of capacitors applied in ferroelectric random access memories (FeRAM) are investigated in this work. Pt and Ir are used as bottom and top electrodes (BE and TE), respectively, in sol-gel Pb(Zr xTi 1-x)O 3 (PZT) based capacitors. Bottom electrodes are found to play a dominant role in the properties of PZT films and capacitors. Capacitors using Pt as bottom electrode have larger remnant polarization (2Pr) than those using Ir which may result from the different orientations of PZT films. The higher Schottky barrier, more dense film and smaller roughness are believed to be the reasons for the better leakage performance of capacitors using Pt as bottom electrodes. Different vacancies types and interface conditions are believed to be the main reasons for the better fatigue (less than 10% initial 2Pr loss after 10 11 fatigue cycles) and better imprint properties of TE/PZT/Ir capacitors. Top electrodes are found to have smaller impact on the properties of capacitors compared with bottom electrodes. A decrease in 2Pr is found when Ir is used as top electrode instead of Pt for PZT/Pt, which is believed to be caused by the stress resulting from lattice mismatch. The different thermal processes that top and bottom electrodes suffered are believed to be the reason for the different impacts they have on capacitors.

Assessing Barriers to the Use of Fall Protection in Small Residential Construction Companies in New Jersey.

PubMed

Borjan, Marija; Patel, Toral; Lefkowitz, Daniel; Campbell, Carla; Lumia, Margaret

2016-05-01

Three focus groups were conducted with residential construction workers from local New Jersey labor organizations to characterize barriers to fall protection use among residential construction contractors who work for companies with fewer than ten employees. Thirty-six residential construction workers volunteered to participate, the average age was thirty-nine years, and twenty-four (67%) were of Hispanic origin. Twelve (33%) of the participants reported having fallen from greater than 6 ft at work and twenty (56%) of the participants had known someone who has fallen from greater than 6 ft. Sixteen (44%) had not been provided with fall protection equipment by their employer and eighteen (50%) reported their current employer had not provided workplace safety training. Factors that created barriers to use of fall protection equipment such as equipment availability, employee/employer relationships, cultural differences, and company size were identified. Results from this study confirm that falls remain a concern among residential construction workers in small companies. © The Author(s) 2015.

49 CFR 571.121 - Standard No. 121; Air brake systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... construction that accommodates harvest containers, a maximum length of 28 feet, and an arrangement of air.... Container chassis trailer means a semitrailer of skeleton construction limited to a bottom frame, one or... containers, so that when the chassis and container are assembled, the units serve the same function as an...

Top Down versus Bottom Up: The Social Construction of the Health Literacy Movement

ERIC Educational Resources Information Center

Huber, Jeffrey T.; Shapiro, Robert M., II; Gillaspy, Mary L.

2012-01-01

The health literacy movement has been socially constructed over time. Unlike the consumer health information movement, which developed with broad public support, the health literacy movement has been fashioned primarily from the top down, initiated by policy makers and imposed on targeted populations. Interest in the health literacy movement has…

3. CONSTRUCTION DETAIL WEST PORTAL SHOWING CONCRETE LINING. NOTE DRILL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. CONSTRUCTION DETAIL WEST PORTAL SHOWING CONCRETE LINING. NOTE DRILL HOLES IN GRANITE AT RIGHT EDGE. US GEOLOGICAL SURVEY BENCHMARK AT BOTTOM CORNER OF SIDEWALK - 4,621 FEET. SLOT IN FAR WALL FOR SEMAPHORE OF OBSOLETE CARBON MONOXIDE WARNING SYSTEM. - Wawona Tunnel, Wawona Road through Turtleback Dome, Yosemite Village, Mariposa County, CA

Towards the design of 3D multiscale instructive tissue engineering constructs: Current approaches and trends.

PubMed

Oliveira, Sara M; Reis, Rui L; Mano, João F

2015-11-01

The design of 3D constructs with adequate properties to instruct and guide cells both in vitro and in vivo is one of the major focuses of tissue engineering. Successful tissue regeneration depends on the favorable crosstalk between the supporting structure, the cells and the host tissue so that a balanced matrix production and degradation are achieved. Herein, the major occurring events and players in normal and regenerative tissue are overviewed. These have been inspiring the selection or synthesis of instructive cues to include into the 3D constructs. We further highlight the importance of a multiscale perception of the range of features that can be included on the biomimetic structures. Lastly, we focus on the current and developing tissue-engineering approaches for the preparation of such 3D constructs: top-down, bottom-up and integrative. Bottom-up and integrative approaches present a higher potential for the design of tissue engineering devices with multiscale features and higher biochemical control than top-down strategies, and are the main focus of this review. Copyright © 2015 Elsevier Inc. All rights reserved.

Clostridium botulinum in Scottish fish farms and farmed trout.

PubMed

Burns, G F; Williams, H

1975-02-01

Rainbow trout and specimens of pond mud were collected from three fish farms and examined for the presence of Clostridium botulinum. Two of the farms were constructed with concrete channels and one was mud-bottomed. Cl. botulinum was isolated only from the mud-bottomed farm (24% of muds), and the isolates were all non-proteolytic type B. The implications of the presence of Cl. botulinum spores in the mud of fish farms is discussed.

RATE OF TCE DEGRADATION IN PASSIVE REACTIVE BARRIERS CONSTRUCTED WITH PLANT MULCH (BIOWALLS)

EPA Science Inventory

This presentation reviews a case study at Altus AFB on the extent of treatment of TCE in a passive reactive barrier constructed with plant mulch. It presents data from a tracer test to estimate the rate of ground water flow at the site, and the residence time of water and TCE in...

Granular flow in silos with moving exit

NASA Astrophysics Data System (ADS)

To, Kiwing

2017-11-01

We conducted granular flow experiments of mono-disperse plastic beads falling out of a cylindrical silos through a circular orifice at the bottom. When the diameter of the orifice is about twice that of the beads, no finite flow rate can be sustained because of clogging at the orifice. We constructed a silo with a bottom that can rotate with respect to the wall of the silo. Then one can rotate the bottom of the silo so that the orifice can rotate (or move in a circle if the orifice is off centered) with respect to the beads. In such a silo with rotating bottom, a finite flow rate can be sustained. While the flow rate Q depends on the angular frequency ω of the rotating bottom as well as the distance R of the orifice from the axis of the silo, Q at different ω and R can be collapsed to a single curve when Q when plotted against the product of ω and R. Nankang, Taipei, Taiwan 11529.

Compressive strength performance of OPS lightweight aggregate concrete containing coal bottom ash as partial fine aggregate replacement

NASA Astrophysics Data System (ADS)

Muthusamy, K.; Mohamad Hafizuddin, R.; Mat Yahaya, F.; Sulaiman, M. A.; Syed Mohsin, S. M.; Tukimat, N. N.; Omar, R.; Chin, S. C.

2018-04-01

Concerns regarding the negative impact towards environment due to the increasing use of natural sand in construction industry and dumping of industrial solid wastes namely coal bottom ash (CBA) and oil palm shell (OPS) has resulted in the development of environmental friendly lightweight concrete. The present study investigates the effect of coal bottom ash as partial fine aggregate replacement towards workability and compressive strength of oil palm shell lightweight aggregate concrete (OPS LWAC). The fresh and mechanical properties of this concrete containing various percentage of coal bottom ash as partial fine aggregate replacement were investigated. The result was compared to OPS LWAC with 100 % sand as a control specimen. The concrete workability investigated by conducting slump test. All specimens were cast in form of cubes and water cured until the testing age. The compressive strength test was carried out at 7 and 28 days. The finding shows that integration of coal bottom ash at suitable proportion enhances the strength of oil palm shell lightweight aggregate concrete.

Leaching behaviour of municipal solid waste incineration bottom ash: From granular material to monolithic concrete.

PubMed

Sorlini, Sabrina; Collivignarelli, Maria Cristina; Abbà, Alessandro

2017-09-01

The aim of this work was to assess the leaching behaviour of the bottom ash derived from municipal solid waste incineration (MSWI) used in concrete production. In particular, the release of pollutants was evaluated by the application of different leaching tests, both on granular materials and monolithic samples (concrete mixtures cast with bottom ash). The results confirmed that, according to Italian regulations, unwashed bottom ashes present critical issues for the use as alternative aggregates in the construction sector due to the excessive release of pollutants; instead, the leachate from washed bottom ashes was similar to natural aggregates. The concentration of pollutants in the leachate from concrete mixtures was lower than regulation limits for reuse. The crushing process significantly influenced the release of pollutants: this behaviour was due both to the increase in surface area and the release of contaminants from cement. Moreover, the increase in contact time (up to 64 days) involved more heavy metals to be released.

A new instrument system to investigate sediment dynamics on continental shelves

USGS Publications Warehouse

Cacchione, D.A.; Drake, D.E.

1979-01-01

A new instrumented tripod, the GEOPROBE system, has been constructed and used to collect time-series data on physical and geological parameters that are important in bottom sediment dynamics on continental shelves. Simultaneous in situ digital recording of pressure, temperature, light scattering, and light transmission, in combination with current velocity profiles measured with a near-bottom vertical array of electromagnetic current meters, is used to correlate bottom shear generated by a variety of oceanic processes (waves, tides, mean flow, etc.) with incipient movement and resuspension of bottom sediment. A bottom camera system that is activated when current speeds exceed preset threshold values provides a unique method to identify initial sediment motion and bed form development. Data from a twenty day deployment of the GEOPROBE system in Norton Sound, Alaska, during the period September 24 - October 14, 1976 show that threshold conditions for sediment movement are commonly exceeded, even in calm weather periods, due to the additive effects of tidal currents, mean circulation, and surface waves. ?? 1979.

Bottom electrodes dependence of microstructures and dielectric properties of compositionally graded (Ba{sub 1-x}Sr{sub x})TiO{sub 3} thin films

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang Tianjin; Wang Jinzhao; Zhang Baishun

2008-03-04

Compositionally graded (Ba{sub 1-x}Sr{sub x})TiO{sub 3} (BST) thin films, with x decreasing from 0.3 to 0, were deposited on Pt/Ti/SiO{sub 2}/Si and Ru/SiO{sub 2}/Si substrates by radio frequency magnetron sputtering technology. The microstructure and dielectric properties of the graded BST thin films were investigated. It was found that the films on Ru electrode have better crystallization, and that RuO{sub 2} is present between the Ru bottom electrode and the graded BST thin films by X-ray diffraction and SEM analysis. Dielectric measurement reveals that the graded BST thin films deposited on Ru bottom electrode have higher dielectric constant and tunability. Themore » enhanced dielectric behavior is attributed to better crystallization as well as smaller space charge capacitance width and the formation of RuO{sub 2} that is more compatible with the BST films. The graded BST films on Ru electrode show higher leakage current due to lower barrier height and rougher surface of bottom electrode.« less

PERMEABLE REACTIVE BARRIER TECHNOLOGIES FOR CONTAMINANT REMEDIATION

EPA Science Inventory

Environmental scientists are generally familiar with the concept of barriers for restricting the movement of contaminant plumes in ground water. Such barriers are typically constructed of highly impermeable emplacements of materials such as grouts, slurries, or sheet pilings to ...

200-BP-1 Prototype Hanford Barrier -- 15 Years of Performance Monitoring

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ward, Anderson L.; Draper, Kathryn E.; Link, Steven O.

2011-09-30

Monitoring is an essential component of engineered barrier system design and operation. A composite capacitive cover, including a capillary break and an evapotranspiration (ET) barrier at the Hanford Site, is generating data that can be used to help resolve these issues. The prototype Hanford barrier was constructed over the 216-B-57 Crib in 1994 to evaluate surface-barrier constructability, construction costs, and physical and hydrologic performance at the field scale. The barrier has been routinely monitored between November 1994 and September 1998 as part of a Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) treatability test of barrier performance formore » the 200 BP 1 Operable Unit. Since FY 1998, monitoring has focused on a more limited set of key water balance, stability, and biotic parameters. In FY 2009, data collection was focused on: (1) water-balance monitoring, consisting of precipitation, runoff, soil moisture storage, and drainage measurements with evapotranspiration calculated by difference; (2) stability monitoring, consisting of asphalt-layer-settlement, basalt-side-slope-stability, and surface-elevation measurements; (3) vegetation dynamics; and (4) animal use. September 2009 marked 15 years since the start of monitoring and the collection of performance data. This report describes the results of monitoring activities during the period October 1, 2008, through September 30, 2009, and summarizes the 15 years of performance data collected from September 1994 through September 2009.« less

Seismic-reflection and sidescan-sonar data collected off eastern Cape Cod, Massachusetts, during April 1979

USGS Publications Warehouse

Knebel, Harley J.

1981-01-01

The U.S. Geological Survey collected 98 line kilometers of single-channel seismic-reflection profiles and sidescan sonar records on the inner shelf of eastern Cape Cod, Massachusetts, during April 1979. The data were obtained during cruise NE-1-79 of the R/V NEECHO. The purposes of the survey were: (1) to study the development of barrier islands; (2) to document the frequency and rate of migration of inlets that breach barrier islands; and (3) to define the characteristics of shoreface ridges on a barrier island.he survey uti I ized two acoustic systems. Information about the bottom was obtained by using an EDO Western model 606 sidescan-sonar system (100 kHz). Profiles of the subbottom were collected by an EG&G Uni boom transducer (400-4,000 Hz) and a Del Norte streamer. Positional control for al I track! ines was provided by a shore-based Miniranger system and by LORAN-C.The quality of the records generally is very good. However, subbottom penetration did vary somewhat from place to place during the survey due to the nature of the bottom sediments and to the presence or absence of buried channels.The original records may be examined at the U.S. Geological Survey, Woods Hole, MA 02543. Microfilm copies of the data are avai I able for purchase from the National Geophysical pnd Solar-Terrestrial Data Center, NOAA/EDIS/NGSDC, Code D621, 325 Broadway, Boulder, CO 80303 (303-497-6338).

Recirculation or artificial aeration in vertical flow constructed wetlands: a comparative study for treating high load wastewater.

PubMed

Foladori, Paola; Ruaben, Jenny; Ortigara, Angela R C

2013-12-01

Vertical subsurface-flow constructed wetlands at pilot-scale have been applied to treat high hydraulic and organic loads by implementing the following configurations: (1) intermittent recirculation of the treated wastewater from the bottom to the top of the bed, (2) intermittent artificial aeration supplied at the bottom of the bed and (3) the combination of both. These configurations were operated with a saturated bottom layer for a 6h-treatment phase, followed by a free drainage phase prior to a new feeding. COD removal efficiency was 85-90% in all the configurations and removed loads were 54-70 gCOD m(-2)d(-1). The aerated and recirculated wetland resulted in a higher total nitrogen removal (8.6 gN m(-2)d(-1)) due to simultaneous nitrification/denitrification, even in the presence of intermittent aeration (6.8 Nm(3)m(-2)d(-1)). The extra investment needed for implementing aeration/recirculation would be compensated for by a reduction of the surface area per population equivalent, which decreased to 1.5m(2)/PE. Copyright © 2013 Elsevier Ltd. All rights reserved.

Evaluation of Schottky barrier height on 4H-SiC m-face \\{ 1\\bar{1}00\\} for Schottky barrier diode wall integrated trench MOSFET

NASA Astrophysics Data System (ADS)

Kobayashi, Yusuke; Ishimori, Hiroshi; Kinoshita, Akimasa; Kojima, Takahito; Takei, Manabu; Kimura, Hiroshi; Harada, Shinsuke

2017-04-01

We proposed an Schottky barrier diode wall integrated trench MOSFET (SWITCH-MOS) for the purposes of shrinking the cell pitch and suppressing the forward degradation of the body diode. A trench Schottky barrier diode (SBD) was integrated into a trench gate MOSFET with a wide shielding p+ region that protected the trench bottoms of both the SBD and the MOS gate from high electrical fields in the off state. The SBD was placed on the trench sidewall of the \\{ 1\\bar{1}00\\} plane (m-face). Static and transient simulations revealed that SWITCH-MOS sufficiently suppressed the bipolar current that induced forward degradation, and we determined that the optimum Schottky barrier height (SBH) was from 0.8 to 2.0 eV. The SBH depends on the crystal planes in 4H-SiC, but the SBH of the m-face was unclear. We fabricated a planar m-face SBD for the first time, and we obtained SBHs from 1.4 to 1.8 eV experimentally with titanium or nickel as a Schottky metal.

Mathematical numeric models for assessing the groundwater pollution from Sanitary landfills

NASA Astrophysics Data System (ADS)

Petrov, Vasil; Stoyanov, Nikolay; Sotinev, Petar

2014-05-01

Landfills are among the most common sources of pollution in ground water. Their widespread deployment, prolonged usage and the serious damage they cause to all of the elements of the environment are the reasons, which make the study of the problem particularly relevant. Most dangerous of all are the open dumps used until the middle of the twentieth century, from which large amounts of liquid emissions flowed freely (landfill infiltrate). In recent decades, the problem is solved by the construction of sanitary landfills in which they bury waste or solid residue from waste utilization plants. The bottom and the sides of the sanitary landfills are covered with a protective waterproof screen made of clay and polyethylene and the landfill infiltrate is led outside through a drainage system. This method of disposal severely limits any leakage of gas and liquid emissions into the environment and virtually eliminates the possibility of contamination. The main topic in the conducted hydrogeological study was a quantitative assessment of groundwater pollution and the environmental effects of re-landfilling of an old open dump into a new sanitary landfill, following the example of the municipal landfill of Asenovgrad, Bulgaria. The study includes: 1.A set of drilling, geophysical and hydrogeological field and laboratory studies on: -the definition and designation of the spatial limits of the main hydrogeological units; -identification of filtration parameters and migration characteristics of the main hydrogeological units; -clarifying the conditions for the sustentation and drainage of groundwater; -determininng the structure of the filtration field; -identifying and assessing the size and the extent of groundwater contamination from the old open dump . 2.Mathematical numeric models of migration and entry conditions of contaminants below the bottom of the landfill unit, with which the natural protection of the geological environment, the protective effect of the engineering barriers of the sanitary landfill, and the potential risk of contamination of the groundwater were evaluated. The migration of contaminants through the zone of aeration and the engineering barriers are modeled with 2D models, and their potential distribution in groundwater - with 3D models. The models simulate the behavior of highly mobile and less mobile contaminants by the example of chloride and ammonium ions (Cl-and NH4 +).The mechanism of mass transfer is set in its full form: convective transport, accompanied by reversible elimination (sorption), mechanical dispersion (longitudinal and transverse), molecular diffusion and dilution. The concentration of the infiltrating under the bottom of the dump unit pollutants is set to exponentially decreasing function, determined by data from the monitoring. Two-dimensional models are developed using the computer program VS2DTI - v.1.3, and three-dimensional models by Modflow and MT3D-MS.dimensional models by Modflow and MT3D-MS.

Thin film encapsulation for flexible AM-OLED: a review

NASA Astrophysics Data System (ADS)

Park, Jin-Seong; Chae, Heeyeop; Chung, Ho Kyoon; In Lee, Sang

2011-03-01

Flexible organic light emitting diode (OLED) will be the ultimate display technology to customers and industries in the near future but the challenges are still being unveiled one by one. Thin-film encapsulation (TFE) technology is the most demanding requirement to prevent water and oxygen permeation into flexible OLED devices. As a polymer substrate does not offer the same barrier performance as glass, the TFE should be developed on both the bottom and top side of the device layers for sufficient lifetimes. This work provides a review of promising thin-film barrier technologies as well as the basic gas diffusion background. Topics include the significance of the device structure, permeation rate measurement, proposed permeation mechanism, and thin-film deposition technologies (Vitex system and atomic layer deposition (ALD)/molecular layer deposition (MLD)) for effective barrier films.

Tunneling with a hydrodynamic pilot-wave model

NASA Astrophysics Data System (ADS)

Nachbin, André; Milewski, Paul A.; Bush, John W. M.

2017-03-01

Eddi et al. [Phys. Rev Lett. 102, 240401 (2009), 10.1103/PhysRevLett.102.240401] presented experimental results demonstrating the unpredictable tunneling of a classical wave-particle association as may arise when a droplet walking across the surface of a vibrating fluid bath approaches a submerged barrier. We here present a theoretical model that captures the influence of bottom topography on this wave-particle association and so enables us to investigate its interaction with barriers. The coupled wave-droplet dynamics results in unpredictable tunneling events. As reported in the experiments by Eddi et al. and as is the case in quantum tunneling [Gamow, Nature (London) 122, 805 (1928), 10.1038/122805b0], the predicted tunneling probability decreases exponentially with increasing barrier width. In the parameter regimes examined, tunneling between two cavities suggests an underlying stationary ergodic process for the droplet's position.

Variation of the phytotoxicity of municipal solid waste incinerator bottom ash on wheat (Triticum aestivum L.) seed germination with leaching conditions.

PubMed

Phoungthong, Khamphe; Zhang, Hua; Shao, Li-Ming; He, Pin-Jing

2016-03-01

Municipal solid waste incinerator bottom ash (MSWIBA) has long been regarded as an alternative building material in the construction industry. However, the pollutants contained in the bottom ash could potentially leach out and contaminate the local environment, which presents an obstacle to the reuse of the materials. To evaluate the environmental feasibility of using MSWIBA as a recycled material in construction, the leaching derived ecotoxicity was assessed. The leaching behavior of MSWIBA under various conditions, including the extractant type, leaching time, liquid-to-solid (L/S) ratio, and leachate pH were investigated, and the phytotoxicity of these leachates on wheat (Triticum aestivum L.) seed germination was determined. Moreover, the correlation between the germination index and the concentrations of various chemical constituents in the MSWIBA leachates was assessed using multivariate statistics with principal component analysis and Pearson's correlation analysis. It was found that, heavy metal concentrations in the leachate were pH and L/S ratio dependent, but were less affected by leaching time. Heavy metals were the main pollutants present in wheat seeds. Heavy metals (especially Ba, Cr, Cu and Pb) had a substantial inhibitory effect on wheat seed germination and root elongation. To safely use MSWIBA in construction, the potential risk and ecotoxicity of leached materials must be addressed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparison and testing of various noise wall materials.

DOT National Transportation Integrated Search

2014-06-01

Noise barriers are a necessary structure along the highway to protect the local residents from excessive : road noise. There are many different materials from which noise barriers can be constructed. As of 2004, the : most widely used noise barrier m...

Barriers and enablers to changing organizational culture in nursing homes.

PubMed

Scalzi, Cynthia C; Evans, Lois K; Barstow, Alan; Hostvedt, Kathryn

2006-01-01

To discuss the barriers and enablers of changing organizational culture in 3 nursing homes undergoing a culture change initiative, and suggest actions for program enhancement. Interview data with staff (n = 64) and families (n = 14) from 3 culture-change facilities in a larger mixed-methods pilot study were used to identify barriers and enablers. The 3 sites ranged from 120 to 139 beds and did not differ in staff characteristics. Barriers included exclusion of nurses from culture-change activities, perceived corporate emphasis on regulatory compliance and the "bottom line," and high turnover of administrators and caregivers. Enablers included a critical mass of "change champions," shared values and goals, resident/family participation, and empowerment at the facility level. Involve all levels of staff, residents, and community in culture-change activities. Align incentives and rewards with the new values. Empower individual homes to make decisions at the facility level. Work with corporate partners to enable rapid translation and implementation of recommendations based on the findings.

Series interconnected photovoltaic cells and method for making same

DOEpatents

Albright, S.P.; Chamberlin, R.R.; Thompson, R.A.

1995-01-31

A novel photovoltaic module and method for constructing the same are disclosed. The module includes a plurality of photovoltaic cells formed on a substrate and laterally separated by interconnection regions. Each cell includes a bottom electrode, a photoactive layer and a top electrode layer. Adjacent cells are connected in electrical series by way of a conductive-buffer line. The buffer line is also useful in protecting the bottom electrode against severing during downstream layer cutting processes. 11 figs.

Reuse potential of low-calcium bottom ash as aggregate through pelletization.

PubMed

Geetha, S; Ramamurthy, K

2010-01-01

Coal combustion residues which include fly ash, bottom ash and boiler slag is one of the major pollutants as these residues require large land area for their disposal. Among these residues, utilization of bottom ash in the construction industry is very low. This paper explains the use of bottom ash through pelletization. Raw bottom ash could not be pelletized as such due to its coarseness. Though pulverized bottom ash could be pelletized, the pelletization efficiency was low, and the aggregates were too weak to withstand the handling stresses. To improve the pelletization efficiency, different clay and cementitious binders were used with bottom ash. The influence of different factors and their interaction effects were studied on the duration of pelletization process and the pelletization efficiency through fractional factorial design. Addition of binders facilitated conversion of low-calcium bottom ash into aggregates. To achieve maximum pelletization efficiency, the binder content and moisture requirements vary with type of binder. Addition of Ca(OH)(2) improved the (i) pelletization efficiency, (ii) reduced the duration of pelletization process from an average of 14-7 min, and (iii) reduced the binder dosage for a given pelletization efficiency. For aggregate with clay binders and cementitious binder, Ca(OH)(2) and binder dosage have significant effect in reducing the duration of pelletization process. 2010 Elsevier Ltd. All rights reserved.

Ground-water, surface-water, and bottom-sediment contamination in the O-field area, Aberdeen Proving Ground, Maryland, and the possible effects of selected remedial actions on ground water

USGS Publications Warehouse

Vroblesky, Don A.; Lorah, Michelle M.; Oliveros, James P.

1995-01-01

Disposal of munitions and chemical-warfare substances has introduced inorganic and organic contaminants to the ground water, surface water, and bottom sediment at O-Field, in the Edgewood area of Aberdeen Proving Ground, Maryland. Contaminants include chloride, arsenic, transition metals, chlorinated aliphatic hydrocarbons, aromatic compounds, and organosulfur and organophosphorus compounds. The hydrologic effects of several remedial actions were estimated by use of a ground-water-flow model. The remedial actions examined were an impermeable covering, encapsulation, subsurface barriers, a ground-water drain, pumping of wells to manage water levels or to remove contaminated ground water for treatment, and no action.

46 CFR 169.323 - Furniture and furnishings.

Code of Federal Regulations, 2010 CFR

2010-10-01

... other material having equivalent fire resistant qualities. (e) Trash receptacles must be constructed of non-combustible materials with solid sides and bottoms and have solid noncombustible covers. Rails and...

46 CFR 169.323 - Furniture and furnishings.

Code of Federal Regulations, 2013 CFR

2013-10-01

... other material having equivalent fire resistant qualities. (e) Trash receptacles must be constructed of non-combustible materials with solid sides and bottoms and have solid noncombustible covers. Rails and...

46 CFR 169.323 - Furniture and furnishings.

Code of Federal Regulations, 2014 CFR

2014-10-01

... other material having equivalent fire resistant qualities. (e) Trash receptacles must be constructed of non-combustible materials with solid sides and bottoms and have solid noncombustible covers. Rails and...

MaxSynBio - Avenues towards creating cells from the bottom up.

PubMed

Schwille, Petra; Spatz, Joachim; Landfester, Katharina; Bodenschatz, Eberhard; Herminghaus, Stephan; Sourjik, Victor; Erb, Tobias; Bastiaens, Philippe; Lipowsky, Reinhard; Hyman, Anthony; Dabrock, Peter; Baret, Jean-Christophe; Vidakovic-Koch, Tanja; Bieling, Peter; Dimova, Rumiana; Mutschler, Hannes; Robinson, Tom; Tang, Dora; Wegner, Seraphine; Sundmacher, Kai

2018-05-11

A large Max Planck-based German research consortium ('MaxSynBio') was formed to investigate living systems from a fundamental perspective. The research program of MaxSynBio relies solely on the bottom-up approach to Synthetic Biology. MaxSynBio focuses on the detailed analysis and understanding of essential processes of life, via their modular reconstitution in minimal synthetic systems. The ultimate goal is to construct a basic living unit entirely from non-living components. The fundamental insights gained from the activities in MaxSynBio can eventually be utilized for establishing a new generation of biotechnological processes, which would be based on synthetic cell constructs that replace natural cells currently used in conventional biotechnology. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Self-organization of maze-like structures via guided wrinkling.

PubMed

Bae, Hyung Jong; Bae, Sangwook; Yoon, Jinsik; Park, Cheolheon; Kim, Kibeom; Kwon, Sunghoon; Park, Wook

2017-06-01

Sophisticated three-dimensional (3D) structures found in nature are self-organized by bottom-up natural processes. To artificially construct these complex systems, various bottom-up fabrication methods, designed to transform 2D structures into 3D structures, have been developed as alternatives to conventional top-down lithography processes. We present a different self-organization approach, where we construct microstructures with periodic and ordered, but with random architecture, like mazes. For this purpose, we transformed planar surfaces using wrinkling to directly use randomly generated ridges as maze walls. Highly regular maze structures, consisting of several tessellations with customized designs, were fabricated by precisely controlling wrinkling with the ridge-guiding structure, analogous to the creases in origami. The method presented here could have widespread applications in various material systems with multiple length scales.

Reactive barrier system for nitrate removal from mine effluents in northern Sweden: Laboratory experiments

NASA Astrophysics Data System (ADS)

Herbert, Roger

2010-05-01

Laboratory column experiments have been conducted to determine nitrate removal rates from mine effluents by denitrification, with the purpose of providing initial data for the construction of a pilot scale reactive barrier system at the Malmberget iron mine, Sweden. Experiments were conducted at several different flow rates at 5C, 10C and room temperature; annual mean temperatures at the Malmberget site lie close to 0C. Columns were filled with an organic substrate consisting of sawdust mixed with sewage sludge, the source of denitrifying bacteria, supported by oven-dried clay pellets. Apparent denitrification rates, calculated from inflow and outflow nitrate concentrations and column hydraulic residence time, ranged from 5 to 13 mg N/L/d, with the lowest rates corresponding to the 5C experiments. These rates are, however, limited to a certain degree by the low flow rate and the supply of electrons acceptors (i.e. nitrate) to denitrifying bacteria. Results from the column experiment have been used to construct a barrier system in Malmberget, Sweden. Trial runs with the pilot-scale barrier will be conducted during 2010, with the purpose of determining the performance of the barrier as mean air temperatures increase from below to above 0C and saturated flow commences in the barrier. The barrier system is constructed as a rectangular container with steel sheet walls (9m length in flow direction, 1.5m deep), and the flow rate will be adjusted to a hydraulic residence time of 1 day. The pilot-scale barrier system currently lies above ground, but a permanent barrier system would be installed below the ground surface so that the system can be maintained at positive temperatures throughout the year.

Fabrication and photocatalytic properties of free-standing TiO{sub 2} nanotube membranes with through-hole morphology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liao Jianjun; Lin Shiwei, E-mail: linsw@hainu.edu.cn; Pan Nengqian

2012-04-15

Anodic growth of TiO{sub 2} nanotubes has recently attracted intensive interests. However, the insulating, closed barrier layer has restricted their feasibility for the applications such as flow-through photocatalytic reactions, biofiltration, and diffusion controlling. In the present work, we fabricated free-standing TiO{sub 2} membranes with through-hole morphology by elevating the anodizing voltage at the end of anodization process. Characterization of the samples was carried out by means of scanning electron microscope, X-ray diffraction and thermogravimetry-differential scanning calorimetry. The experimental results show that the TiO{sub 2} membranes start to transform from amorphous phase to anatase at 300 Degree-Sign C, and the phasemore » transformation from anatase to rutile starts at 650 Degree-Sign C. In addition, photocatalytic degradation of rhodamine B by the TiO{sub 2} membranes with closed bottoms and opened bottoms has also been systematically investigated. As compared to TiO{sub 2} membranes with closed bottoms, TiO{sub 2} membranes with opened bottoms exhibited superior photocatalytic activity due to its better access for rhodamine B molecules as well as the enhanced light harvesting and electron collection efficiencies. Highlights: Black-Right-Pointing-Pointer The closed bottoms were opened by elevating the anodizing voltage. Black-Right-Pointing-Pointer Phase transformation from anatase to rutile starts at 650 Degree-Sign C. Black-Right-Pointing-Pointer TiO{sub 2} membranes in the anatase form have a better catalytic performance. Black-Right-Pointing-Pointer Opened-bottom TiO{sub 2} membranes with exhibited superior photocatalytic activity.« less

Overcoming Codes and Standards Barriers to Innovations in Building Energy Efficiency

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cole, Pamala C.; Gilbride, Theresa L.

2015-02-15

In this journal article, the authors discuss approaches to overcoming building code barriers to energy-efficiency innovations in home construction. Building codes have been a highly motivational force for increasing the energy efficiency of new homes in the United States in recent years. But as quickly as the codes seem to be changing, new products are coming to the market at an even more rapid pace, sometimes offering approaches and construction techniques unthought of when the current code was first proposed, which might have been several years before its adoption by various jurisdictions. Due to this delay, the codes themselves canmore » become barriers to innovations that might otherwise be helping to further increase the efficiency, comfort, health or durability of new homes. . The U.S. Department of Energy’s Building America, a program dedicated to improving the energy efficiency of America’s housing stock through research and education, is working with the U.S. housing industry through its research teams to help builders identify and remove code barriers to innovation in the home construction industry. The article addresses several approaches that builders use to achieve approval for innovative building techniques when code barriers appear to exist.« less

Institutional Motivations and Barriers to the Construction of Green Buildings on Campus: A Case Study of the University of Waterloo, Ontario

ERIC Educational Resources Information Center

Richardson, Gregory R. A.; Lynes, Jennifer K.

2007-01-01

Purpose: To explore the barriers and motivations to the construction of green buildings at the University of Waterloo (UW) by documenting and analysing the UW building process. Design/methodology/approach: The authors conducted 13 semi-structured in-depth interviews with key UW individuals as well as analyzing numerous internal reports in order to…

ETR COMPLEX. CAMERA FACING SOUTH. FROM BOTTOM OF VIEW TO ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ETR COMPLEX. CAMERA FACING SOUTH. FROM BOTTOM OF VIEW TO TOP: MTR, MTR SERVICE BUILDING, ETR CRITICAL FACILITY, ETR CONTROL BUILDING (ATTACHED TO ETR), ETR BUILDING (HIGH-BAY), COMPRESSOR BUILDING (ATTACHED AT LEFT OF ETR), HEAT EXCHANGER BUILDING (JUST BEYOND COMPRESSOR BUILDING), COOLING TOWER PUMP HOUSE, COOLING TOWER. OTHER BUILDINGS ARE CONTRACTORS' CONSTRUCTION BUILDINGS. INL NEGATIVE NO. 56-4105. Unknown Photographer, ca. 1956 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID

Hartwell Lake Project, Savannah River, Georgia and South Carolina. Rehabilitation of Clemson Upper Diversion Dam. Construction Foundation Report. Volume 2. Appendices B thru E

DTIC Science & Technology

1989-08-01

remove by gravity -washed out 585.8 i -- 89. 2 gneiss from inner - ibarrel Bottom of hole 89.2’ Tape depth 89.0’ 90 -0 I-Note: 6-7-84 water level after...barrel and5 _-_89.3 washed all meterial Bottom of hole 89.3’ left in outer barrel- 90 out of barrel befor- drilling for pull I Tape depth 89.0’ Note

Structural system reliability calculation using a probabilistic fault tree analysis method

NASA Technical Reports Server (NTRS)

Torng, T. Y.; Wu, Y.-T.; Millwater, H. R.

1992-01-01

The development of a new probabilistic fault tree analysis (PFTA) method for calculating structural system reliability is summarized. The proposed PFTA procedure includes: developing a fault tree to represent the complex structural system, constructing an approximation function for each bottom event, determining a dominant sampling sequence for all bottom events, and calculating the system reliability using an adaptive importance sampling method. PFTA is suitable for complicated structural problems that require computer-intensive computer calculations. A computer program has been developed to implement the PFTA.

18th Annual School Construction Report, 2013

ERIC Educational Resources Information Center

Abramson, Paul

2013-01-01

The bottom line on school construction in 2012 is that total spending edged up slightly from the previous year, (to $12.9 billion from $12.2 billion), but the spending for new schools declined from $6.9 billion to $6.177 billion. The increase in overall spending was attributable to more spending for additions and a major increase in spending for…

Constructing Educational Quality in the Arab Region: A Bottom-Up Critique of Regional Educational Governance

ERIC Educational Resources Information Center

Morgan, Clara

2017-01-01

The article challenges the deficit view in which education in the Arab region is portrayed by examining the process of educational regionalisation. It takes as its case study the Arab Regional Agenda for Improving Educational Quality in order to explore the construction of an educational quality space that uses data as a governance model. Drawing…

5. CONSTRUCTION PROGRESS VIEW OF ASSEMBLY USED TO RAISE AND ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. CONSTRUCTION PROGRESS VIEW OF ASSEMBLY USED TO RAISE AND LOWER FUEL ELEMENTS. TAKEN FROM TOP OF SHIELDING TANK WITH CAMERA POINTING TOWARDS BOTTOM OF TANK. SHOWS LADDER, SQUARE LIFTING FRAME, FUEL ELEMENT HOLDERS, AND CABLE CYLINDERS. INEL PHOTO NUMBER 65-5434, TAKEN OCTOBER 20, 1965. - Idaho National Engineering Laboratory, Advanced Reentry Vehicle Fusing System, Scoville, Butte County, ID

Monolithic barrier-all-around high electron mobility transistor with planar GaAs nanowire channel.

PubMed

Miao, Xin; Zhang, Chen; Li, Xiuling

2013-06-12

High-quality growth of planar GaAs nanowires (NWs) with widths as small as 35 nm is realized by comprehensively mapping the parameter space of group III flow, V/III ratio, and temperature as the size of the NWs scales down. Using a growth mode modulation scheme for the NW and thin film barrier layers, monolithically integrated AlGaAs barrier-all-around planar GaAs NW high electron mobility transistors (NW-HEMTs) are achieved. The peak extrinsic transconductance, drive current, and effective electron velocity are 550 μS/μm, 435 μA/μm, and ~2.9 × 10(7) cm/s, respectively, at 2 V supply voltage with a gate length of 120 nm. The excellent DC performance demonstrated here shows the potential of this bottom-up planar NW technology for low-power high-speed very-large-scale-integration (VLSI) circuits.

Scanning Probe Microscopy on heterogeneous CaCu3Ti4O12 thin films

PubMed Central

2011-01-01

The conductive atomic force microscopy provided a local characterization of the dielectric heterogeneities in CaCu3Ti4O12 (CCTO) thin films deposited by MOCVD on IrO2 bottom electrode. In particular, both techniques have been employed to clarify the role of the inter- and sub-granular features in terms of conductive and insulating regions. The microstructure and the dielectric properties of CCTO thin films have been studied and the evidence of internal barriers in CCTO thin films has been provided. The role of internal barriers and the possible explanation for the extrinsic origin of the giant dielectric response in CCTO has been evaluated. PMID:21711646

Scanning Probe Microscopy on heterogeneous CaCu3Ti4O12 thin films

NASA Astrophysics Data System (ADS)

Fiorenza, Patrick; Lo Nigro, Raffaella; Raineri, Vito

2011-12-01

The conductive atomic force microscopy provided a local characterization of the dielectric heterogeneities in CaCu3Ti4O12 (CCTO) thin films deposited by MOCVD on IrO2 bottom electrode. In particular, both techniques have been employed to clarify the role of the inter- and sub-granular features in terms of conductive and insulating regions. The microstructure and the dielectric properties of CCTO thin films have been studied and the evidence of internal barriers in CCTO thin films has been provided. The role of internal barriers and the possible explanation for the extrinsic origin of the giant dielectric response in CCTO has been evaluated.

Scanning Probe Microscopy on heterogeneous CaCu3Ti4O12 thin films.

PubMed

Fiorenza, Patrick; Lo Nigro, Raffaella; Raineri, Vito

2011-02-04

The conductive atomic force microscopy provided a local characterization of the dielectric heterogeneities in CaCu3Ti4O12 (CCTO) thin films deposited by MOCVD on IrO2 bottom electrode. In particular, both techniques have been employed to clarify the role of the inter- and sub-granular features in terms of conductive and insulating regions. The microstructure and the dielectric properties of CCTO thin films have been studied and the evidence of internal barriers in CCTO thin films has been provided. The role of internal barriers and the possible explanation for the extrinsic origin of the giant dielectric response in CCTO has been evaluated.

Electric control of wave vector filtering in a hybrid magnetic-electric-barrier nanostructure

NASA Astrophysics Data System (ADS)

Kong, Yong-Hong; Lu, Ke-Yu; He, Ya-Ping; Liu, Xu-Hui; Fu, Xi; Li, Ai-Hua

2018-06-01

We theoretically investigate how to manipulate the wave vector filtering effect by a traverse electric field for electrons across a hybrid magnetic-electric-barrier nanostructure, which can be experimentally realized by depositing a ferromagnetic stripe and a Schottky-metal stripe on top and bottom of a GaAs/Al x Ga1- x As heterostructure, respectively. The wave vector filtering effect is found to be related closely to the applied electric field. Moreover, the wave vector filtering efficiency can be manipulated by changing direction or adjusting strength of the traverse electric field. Therefore, such a nanostructure can be employed as an electrically controllable electron-momentum filter for nanoelectronics applications.

Application of underwater spectrometric system for survey of ponds of the MR reactor (NRC Kurchatov institute)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stepanov, Vyacheslav; Potapov, Victor; Safronov, Alexey

2013-07-01

The underwater spectrometric system for survey the bottom of material science multi-loop reactor MR ponds was elaborated. This system uses CdZnTe (CZT) detectors that allow for spectrometric measurements in high radiation fields. The underwater system was used in the spectrometric survey of the bottom of the MR reactor pool, as well as in the survey located in the MR storage pool of highly radioactive containers and parts of the reactor construction. As a result of these works irradiated nuclear fuel was detected on the bottom of pools, and obtained estimates of the effective surface activity detected radionuclides and created bymore » them the dose rate. (authors)« less

Physical and numerical modeling of hydrophysical proceses on the site of underwater pipelines

NASA Astrophysics Data System (ADS)

Garmakova, M. E.; Degtyarev, V. V.; Fedorova, N. N.; Shlychkov, V. A.

2018-03-01

The paper outlines issues related to ensuring the exploitation safety of underwater pipelines that are at risk of accidents. The performed research is based on physical and mathematical modeling of local bottom erosion in the area of pipeline location. The experimental studies were performed on the basis of the Hydraulics Laboratory of the Department of Hydraulic Engineering Construction, Safety and Ecology of NSUACE (Sibstrin). In the course of physical experiments it was revealed that the intensity of the bottom soil reforming depends on the deepening of the pipeline. The ANSYS software has been used for numerical modeling. The process of erosion of the sandy bottom was modeled under the pipeline. Comparison of computational results at various mass flow rates was made.

Development of Real-time Tsunami Inundation Forecast Using Ocean Bottom Tsunami Networks along the Japan Trench

NASA Astrophysics Data System (ADS)

Aoi, S.; Yamamoto, N.; Suzuki, W.; Hirata, K.; Nakamura, H.; Kunugi, T.; Kubo, T.; Maeda, T.

2015-12-01

In the 2011 Tohoku earthquake, in which huge tsunami claimed a great deal of lives, the initial tsunami forecast based on hypocenter information estimated using seismic data on land were greatly underestimated. From this lesson, NIED is now constructing S-net (Seafloor Observation Network for Earthquakes and Tsunamis along the Japan Trench) which consists of 150 ocean bottom observatories with seismometers and pressure gauges (tsunamimeters) linked by fiber optic cables. To take full advantage of S-net, we develop a new methodology of real-time tsunami inundation forecast using ocean bottom observation data and construct a prototype system that implements the developed forecasting method for the Pacific coast of Chiba prefecture (Sotobo area). We employ a database-based approach because inundation is a strongly non-linear phenomenon and its calculation costs are rather heavy. We prepare tsunami scenario bank in advance, by constructing the possible tsunami sources, and calculating the tsunami waveforms at S-net stations, coastal tsunami heights and tsunami inundation on land. To calculate the inundation for target Sotobo area, we construct the 10-m-mesh precise elevation model with coastal structures. Based on the sensitivities analyses, we construct the tsunami scenario bank that efficiently covers possible tsunami scenarios affecting the Sotobo area. A real-time forecast is carried out by selecting several possible scenarios which can well explain real-time tsunami data observed at S-net from tsunami scenario bank. An advantage of our method is that tsunami inundations are estimated directly from the actual tsunami data without any source information, which may have large estimation errors. In addition to the forecast system, we develop Web services, APIs, and smartphone applications and brush them up through social experiments to provide the real-time tsunami observation and forecast information in easy way to understand toward urging people to evacuate.

The Barriers and Causes of Building Information Modelling Usage for Interior Design Industry

NASA Astrophysics Data System (ADS)

Hamid, A. B. Abd; Taib, M. Z. Mohd; Razak, A. H. N. Abdul; Embi, M. R.

2017-12-01

Building Information Modeling (BIM) has since developed alongside the improvement in the construction industry, purposely to simulate the design, management, construction and documentation. It facilitates and monitors the construction through visualization and emphasizes on various inputs to virtually design and construct a building using specific software. This study aims to identify and elaborate barriers of BIM usage in interior design industry in Malaysia. This study is initiated with a pilot survey utilising sixteen respondents that has been randomly chosen. Respondents are attached with interior design firms that are registered by Lembaga Arkitek Malaysia (LAM). The research findings are expected to provide significant information to encourage BIM adoption among interior design firms.

40 CFR 264.1100 - Applicability.

Code of Federal Regulations, 2014 CFR

2014-07-01

... designed and constructed of materials to prevent migration of hazardous constituents into the barrier; (2... materials to prevent migration of hazardous constituents into the barrier, with a leak detection and liquid...

40 CFR 264.1100 - Applicability.

Code of Federal Regulations, 2013 CFR

2013-07-01

... designed and constructed of materials to prevent migration of hazardous constituents into the barrier; (2... materials to prevent migration of hazardous constituents into the barrier, with a leak detection and liquid...

40 CFR 264.1100 - Applicability.

Code of Federal Regulations, 2012 CFR

2012-07-01

... designed and constructed of materials to prevent migration of hazardous constituents into the barrier; (2... materials to prevent migration of hazardous constituents into the barrier, with a leak detection and liquid...

40 CFR 264.1100 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-07-01

... designed and constructed of materials to prevent migration of hazardous constituents into the barrier; (2... materials to prevent migration of hazardous constituents into the barrier, with a leak detection and liquid...

40 CFR 264.1100 - Applicability.

Code of Federal Regulations, 2010 CFR

2010-07-01

... designed and constructed of materials to prevent migration of hazardous constituents into the barrier; (2... materials to prevent migration of hazardous constituents into the barrier, with a leak detection and liquid...

Stimulating a Sustainable Construction through Holistic BIM Adoption: The Root Causes of Recurring Low BIM Adoption in Malaysia

NASA Astrophysics Data System (ADS)

Mamter, S.; Abdul-Aziz, AR; Mamat, ME

2017-06-01

Fostering the Building Information Modelling (BIM) implementation is one of Malaysia sustainable strategies towards greener construction. Hence, the Eleventh Malaysia plan focuses on transforming construction industry through the increase of technology adoption in order to enhance construction productivity. Therefore, there is a growing and urgent demand to provide BIM competent. However, a significant number of parties are reluctant to develop and invest in BIM due to unsolved root causes. Scholars have identified barriers relating to the infancy stage of BIM adoption in Malaysia. Unfortunately, there is a lack of study to explore deeper the root causes of recurring for the barriers anticipate the low BIM adoption. This paper attempts to delve into the initiatives of BIM stake players in fostering BIM adoption and to determine the root causes of recurring barriers due to low BIM adoption. The study adopted the semi-structured interviews which involved BIM stake players as a sample population. From the findings, authors revealed four root causes of recurring barriers; absence of BIM policy and BIM compulsion, poor holistic readiness, software integration competition strategy, and reluctant in sharing knowledge. The findings espoused here are preliminary and more results are expected to emerge as the research progresses.

Bottom-up construction of a superstructure in a porous uranium-organic crystal

NASA Astrophysics Data System (ADS)

Li, Peng; Vermeulen, Nicolaas A.; Malliakas, Christos D.; Gómez-Gualdrón, Diego A.; Howarth, Ashlee J.; Mehdi, B. Layla; Dohnalkova, Alice; Browning, Nigel D.; O'Keeffe, Michael; Farha, Omar K.

2017-05-01

Bottom-up construction of highly intricate structures from simple building blocks remains one of the most difficult challenges in chemistry. We report a structurally complex, mesoporous uranium-based metal-organic framework (MOF) made from simple starting components. The structure comprises 10 uranium nodes and seven tricarboxylate ligands (both crystallographically nonequivalent), resulting in a 173.3-angstrom cubic unit cell enclosing 816 uranium nodes and 816 organic linkers—the largest unit cell found to date for any nonbiological material. The cuboctahedra organize into pentagonal and hexagonal prismatic secondary structures, which then form tetrahedral and diamond quaternary topologies with unprecedented complexity. This packing results in the formation of colossal icosidodecahedral and rectified hexakaidecahedral cavities with internal diameters of 5.0 nanometers and 6.2 nanometers, respectively—ultimately giving rise to the lowest-density MOF reported to date.

Experimental and numerical investigations on reliability of air barrier on oil containment in flowing water.

PubMed

Lu, Jinshu; Xu, Zhenfeng; Xu, Song; Xie, Sensen; Wu, Haoxiao; Yang, Zhenbo; Liu, Xueqiang

2015-06-15

Air barriers have been recently developed and employed as a new type of oil containment boom. This paper presents systematic investigations on the reliability of air barriers on oil containments with the involvement of flowing water, which represents the commonly-seen shearing current in reality, by using both laboratory experiments and numerical simulations. Both the numerical and experimental investigations are carried out in a model scale. In the investigations, a submerged pipe with apertures is installed near the bottom of a tank to generate the air bubbles forming the air curtain; and, the shearing water flow is introduced by a narrow inlet near the mean free surface. The effects of the aperture configurations (including the size and the spacing of the aperture) and the location of the pipe on the effectiveness of the air barrier on preventing oil spreading are discussed in details with consideration of different air discharges and velocities of the flowing water. The research outcome provides a foundation for evaluating and/or improve the reliability of a air barrier on preventing spilled oil from further spreading. Copyright © 2015 Elsevier Ltd. All rights reserved.

Groundwater Salinity Simulation of a Subsurface Reservoir in Taiwan

NASA Astrophysics Data System (ADS)

Fang, H. T.

2015-12-01

The subsurface reservoir is located in Chi-Ken Basin, Pescadores (a group islands located at western part of Taiwan). There is no river in these remote islands and thus the freshwater supply is relied on the subsurface reservoir. The basin area of the subsurface reservoir is 2.14 km2 , discharge of groundwater is 1.27×106m3 , annual planning water supplies is 7.9×105m3 , which include for domestic agricultural usage. The annual average temperature is 23.3oC, average moisture is 80~85%, annual average rainfall is 913 mm, but ET rate is 1975mm. As there is no single river in the basin; the major recharge of groundwater is by infiltration. Chi-Ken reservoir is the first subsurface reservoir in Taiwan. Originally, the water quality of the reservoir is good. The reservoir has had the salinity problem since 1991 and it became more and more serious from 1992 until 1994. Possible reason of the salinity problem was the shortage of rainfall or the leakage of the subsurface barrier which caused the seawater intrusion. The present study aimed to determine the leakage position of subsurface barrier that caused the salinity problem. In order to perform the simulation for different possible leakage position of the subsurface reservoir, a Groundwater Modeling System (GMS) is used to define soils layer data, hydro-geological parameters, initial conditions, boundary conditions and the generation of three dimension meshes. A three dimension FEMWATER(Yeh , 1996) numerical model was adopted to find the possible leakage position of the subsurface barrier and location of seawater intrusion by comparing the simulation of different possible leakage with the observations. 1.By assuming the leakage position in the bottom of barrier, the simulated numerical result matched the observation better than the other assumed leakage positions. It showed that the most possible leakage position was at the bottom of the barrier. 2.The research applied three dimension FEMWATER and GMS as an interface to input parameter. The simulation of water level and chloride concentration already showed the real situation, and the result can be applied to the future study of the Chi-Ken subsurface reservoir salinity problems.

Modular assembly for supporting, straining, and directing flow to a core in a nuclear reactor

DOEpatents

Pennell, William E.

1977-01-01

A reactor core support arrangement for supporting, straining, and providing fluid flow to the core and periphery of a nuclear reactor during normal operation. A plurality of removable inlet modular units are contained within permanent liners in the lower supporting plate of the reactor vessel lower internals. During normal operation (1) each inlet modular unit directs main coolant flow to a plurality of core assemblies, the latter being removably supported in receptacles in the upper portion of the modular unit and (2) each inlet modular unit may direct bypass flow to a low pressure annular region of the reactor vessel. Each inlet modular unit may include special fluid seals interposed between mating surfaces of the inlet modular units and the core assemblies and between the inlet modular units and the liners, to minimize leakage and achieve an hydraulic balance. Utilizing the hydraulic balance, the modular units are held in the liners and the assemblies are held in the modular unit receptacles by their own respective weight. Included as part of the permanent liners below the horizontal support plate are generally hexagonal axial debris barriers. The axial debris barriers collectively form a bottom boundary of a secondary high pressure plenum, the upper boundary of which is the bottom surface of the horizontal support plate. Peripheral liners include radial debris barriers which collectively form a barrier against debris entry radially. During normal operation primary coolant inlet openings in the liner, below the axial debris barriers, pass a large amount of coolant into the inlet modular units, and secondary coolant inlet openings in the portion of the liners within the secondary plenum pass a small amount of coolant into the inlet modular units. The secondary coolant inlet openings also provide alternative coolant inlet flow paths in the unlikely event of blockage of the primary inlet openings. The primary inlet openings have characteristics which limit the entry of debris and minimize the potential for debris entering the primary inlets blocking the secondary inlets from inside the modular unit.

Energy-Efficient Phase-Change Memory with Graphene as a Thermal Barrier.

PubMed

Ahn, Chiyui; Fong, Scott W; Kim, Yongsung; Lee, Seunghyun; Sood, Aditya; Neumann, Christopher M; Asheghi, Mehdi; Goodson, Kenneth E; Pop, Eric; Wong, H-S Philip

2015-10-14

Phase-change memory (PCM) is an important class of data storage, yet lowering the programming current of individual devices is known to be a significant challenge. Here we improve the energy-efficiency of PCM by placing a graphene layer at the interface between the phase-change material, Ge2Sb2Te5 (GST), and the bottom electrode (W) heater. Graphene-PCM (G-PCM) devices have ∼40% lower RESET current compared to control devices without the graphene. This is attributed to the graphene as an added interfacial thermal resistance which helps confine the generated heat inside the active PCM volume. The G-PCM achieves programming up to 10(5) cycles, and the graphene could further enhance the PCM endurance by limiting atomic migration or material segregation at the bottom electrode interface.

Biomimetic proteolipid vesicles for targeting inflamed tissues

NASA Astrophysics Data System (ADS)

Molinaro, R.; Corbo, C.; Martinez, J. O.; Taraballi, F.; Evangelopoulos, M.; Minardi, S.; Yazdi, I. K.; Zhao, P.; De Rosa, E.; Sherman, M. B.; de Vita, A.; Toledano Furman, N. E.; Wang, X.; Parodi, A.; Tasciotti, E.

2016-09-01

A multitude of micro- and nanoparticles have been developed to improve the delivery of systemically administered pharmaceuticals, which are subject to a number of biological barriers that limit their optimal biodistribution. Bioinspired drug-delivery carriers formulated by bottom-up or top-down strategies have emerged as an alternative approach to evade the mononuclear phagocytic system and facilitate transport across the endothelial vessel wall. Here, we describe a method that leverages the advantages of bottom-up and top-down strategies to incorporate proteins derived from the leukocyte plasma membrane into lipid nanoparticles. The resulting proteolipid vesicles--which we refer to as leukosomes--retained the versatility and physicochemical properties typical of liposomal formulations, preferentially targeted inflamed vasculature, enabled the selective and effective delivery of dexamethasone to inflamed tissues, and reduced phlogosis in a localized model of inflammation.

Constraining Earthquake Source Parameters in Rupture Patches and Rupture Barriers on Gofar Transform Fault, East Pacific Rise from Ocean Bottom Seismic Data

NASA Astrophysics Data System (ADS)

Moyer, P. A.; Boettcher, M. S.; McGuire, J. J.; Collins, J. A.

2015-12-01

On Gofar transform fault on the East Pacific Rise (EPR), Mw ~6.0 earthquakes occur every ~5 years and repeatedly rupture the same asperity (rupture patch), while the intervening fault segments (rupture barriers to the largest events) only produce small earthquakes. In 2008, an ocean bottom seismometer (OBS) deployment successfully captured the end of a seismic cycle, including an extensive foreshock sequence localized within a 10 km rupture barrier, the Mw 6.0 mainshock and its aftershocks that occurred in a ~10 km rupture patch, and an earthquake swarm located in a second rupture barrier. Here we investigate whether the inferred variations in frictional behavior along strike affect the rupture processes of 3.0 < M < 4.5 earthquakes by determining source parameters for 100 earthquakes recorded during the OBS deployment.Using waveforms with a 50 Hz sample rate from OBS accelerometers, we calculate stress drop using an omega-squared source model, where the weighted average corner frequency is derived from an empirical Green's function (EGF) method. We obtain seismic moment by fitting the omega-squared source model to the low frequency amplitude of individual spectra and account for attenuation using Q obtained from a velocity model through the foreshock zone. To ensure well-constrained corner frequencies, we require that the Brune [1970] model provides a statistically better fit to each spectral ratio than a linear model and that the variance is low between the data and model. To further ensure that the fit to the corner frequency is not influenced by resonance of the OBSs, we require a low variance close to the modeled corner frequency. Error bars on corner frequency were obtained through a grid search method where variance is within 10% of the best-fit value. Without imposing restrictive selection criteria, slight variations in corner frequencies from rupture patches and rupture barriers are not discernable. Using well-constrained source parameters, we find an average stress drop of 5.7 MPa in the aftershock zone compared to values of 2.4 and 2.9 MPa in the foreshock and swarm zones respectively. The higher stress drops in the rupture patch compared to the rupture barriers reflect systematic differences in along strike fault zone properties on Gofar transform fault.

Barriers and Enablers to Implementation of Dietary Guidelines in Early Childhood Education Centers in Australia: Application of the Theoretical Domains Framework.

PubMed

Grady, Alice; Seward, Kirsty; Finch, Meghan; Fielding, Alison; Stacey, Fiona; Jones, Jannah; Wolfenden, Luke; Yoong, Sze Lin

2018-03-01

To identify perceived barriers and enablers to implementation of dietary guidelines reported by early childhood education center cooks, and barriers and enablers associated with greater implementation based on assessment of center menu compliance. Cross-sectional telephone interview. Early childhood education centers, New South Wales, Australia. A total of 202 cooks responsible for menu planning; 70 centers provided a menu for review of compliance with dietary guidelines. Barriers and enablers to dietary guideline implementation were determined using a tool assessing constructs of the Theoretical Domains Framework (TDF). Higher scores (≥6) for each construct indicated enablers to guideline implementation; lower scores (<6) suggested barriers. Multivariable linear regression identified TDF constructs associated with greater guideline implementation. Scores were lowest for reinforcement (mean, 5.85) and goals (mean, 5.89) domains, and highest for beliefs about consequences (mean, 6.51) and social/professional role and identity (mean, 6.50). The skills domain was positively associated with greater implementation of guidelines based on menu review (P = .01). Cooks perceived social/professional role and identity, and beliefs about consequences to be enablers to dietary guideline implementation; however, only the skills domain was associated with greater implementation. There are opportunities to target the incongruence in perceptions vs reality of the barriers and enablers to implementation. Future research could examine the utility of the TDF to identify barriers and enablers to implementation to inform intervention development and for evaluating interventions to examine intervention mechanisms. Copyright © 2017 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

A review on the current issues and barriers of Industrialised Building System (IBS) adoption in Malaysia’s construction industry

NASA Astrophysics Data System (ADS)

Amin, M. A. Mohd; Abas, N. H.; Shahidan, S.; Rahmat, M. H.; Suhaini, N. A.; Nagapan, S.; Rahim, R. Abdul

2017-11-01

Malaysia considers the construction industry as one of the main contributors to its Gross Domestic Product (GDP). However, there are some unresolved issues arising from the ongoing and widespread adoption of the conventional method of construction such as the resultant fragmentation of the industry itself; delays in production and delivery time of unnecessary wastages and lack of sustainability practice. Malaysian Government has been continuously encouraging the industry to use, partly or if not wholly, the Industrialized Building System (IBS), which is considered to be an important part of sustainable construction initiative. IBS was introduced to Malaysia as the solution to issues related to dependencies of foreign workers, raising demand for affordable accommodations and improving image, quality and productivity of construction industry. However, the IBS adoption in Malaysia remains low. This paper presents the review of the current issues and barriers of IBS adoption in Malaysian construction industry.

18 CFR 1304.207 - Channel excavation on TVA-owned residential access shoreland.

Code of Federal Regulations, 2010 CFR

2010-04-01

... Resources TENNESSEE VALLEY AUTHORITY APPROVAL OF CONSTRUCTION IN THE TENNESSEE RIVER SYSTEM AND REGULATION... the reservoir bottom is exposed and dry. (h) Spoil material from channel excavations must be placed in...

Elastic Bottom Propagation Mechanisms Investigated by Parabolic Equation Methods

DTIC Science & Technology

2014-09-30

channel propagation of oceanic T waves from seismic sources in the presence of intervening seamounts or coral reef barriers is established using elastic PE...environments in the form of scattering at an elastic interface, oceanic T - waves , and Scholte waves . OBJECTIVES To implement explosive and earthquake...oceanic T - waves , which are acoustic waves that result from earthquake or buried explosive sources, and Rayleigh-type waves along the ocean floor, whose

2D Vertical Heterostructures for Novel Tunneling Device Applications

DTIC Science & Technology

2017-03-01

controlled by a combination of the drain-source voltage bias (VDS) and the top and bottom gate biases (VTG and VBG, respectively). The drain-source...properties that can potentially overcome some of the limitations of epitaxial 3D semiconductor heterostructures. Simulations of 2D...interlayer barrier, such as h-BN, a high-k dielectric material, or a van der Waal gap. Under appropriate bias conditions, charge carriers can tunnel

REMEDIATION OF TCE-CONTAMINATED GROUNDWATER BY A PERMEABLE REACTIVE BARRIER FILLED WITH PLANT MULCH (BIOWALL)

EPA Science Inventory

A pilot-scale permeable reactive barrier filled with plant mulch was installed at Altus Air Force Base (in Oklahoma, USA) to treat trichloroethylene (TCE) contamination in ground water emanating from a landfill. The barrier was constructed in June 2002. It was 139 meters long, 7 ...

Barriers to College Access for Latino/a Adolescents: A Comparison of Theoretical Frameworks

ERIC Educational Resources Information Center

Gonzalez, Laura M.

2015-01-01

A comprehensive description of barriers to college access for Latino/a adolescents is an important step toward improving educational outcomes. However, relevant scholarship on barriers has not been synthesized in a way that promotes coherent formulation of intervention strategies or constructive scholarly discussion. The goal of this article is to…

34 CFR 75.617 - Compliance with the Coastal Barrier Resources Act.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 34 Education 1 2010-07-01 2010-07-01 false Compliance with the Coastal Barrier Resources Act. 75.617 Section 75.617 Education Office of the Secretary, Department of Education DIRECT GRANT PROGRAMS What Conditions Must Be Met by a Grantee? Construction § 75.617 Compliance with the Coastal Barrier...

46 CFR 38.05-1 - Design and construction of vessels-general-TB/ALL.

Code of Federal Regulations, 2012 CFR

2012-10-01

... so arranged as to prevent the flow of cargo vapor from the weather deck into such spaces. In this... secondary barrier is required, the material of that barrier and of contiguous hull structure shall have... within the secondary barrier. Materials used in the fabrication of the cargo containment and handling...

46 CFR 38.05-1 - Design and construction of vessels-general-TB/ALL.

Code of Federal Regulations, 2013 CFR

2013-10-01

... so arranged as to prevent the flow of cargo vapor from the weather deck into such spaces. In this... secondary barrier is required, the material of that barrier and of contiguous hull structure shall have... within the secondary barrier. Materials used in the fabrication of the cargo containment and handling...

46 CFR 38.05-1 - Design and construction of vessels-general-TB/ALL.

Code of Federal Regulations, 2014 CFR

2014-10-01

... so arranged as to prevent the flow of cargo vapor from the weather deck into such spaces. In this... secondary barrier is required, the material of that barrier and of contiguous hull structure shall have... within the secondary barrier. Materials used in the fabrication of the cargo containment and handling...

Effect of dual-dielectric hydrogen-diffusion barrier layers on the performance of low-temperature processed transparent InGaZnO thin-film transistors

NASA Astrophysics Data System (ADS)

Tari, Alireza; Wong, William S.

2018-02-01

Dual-dielectric SiOx/SiNx thin-film layers were used as back-channel and gate-dielectric barrier layers for bottom-gate InGaZnO (IGZO) thin-film transistors (TFTs). The concentration profiles of hydrogen, indium, gallium, and zinc oxide were analyzed using secondary-ion mass spectroscopy characterization. By implementing an effective H-diffusion barrier, the hydrogen concentration and the creation of H-induced oxygen deficiency (H-Vo complex) defects during the processing of passivated flexible IGZO TFTs were minimized. A bilayer back-channel passivation layer, consisting of electron-beam deposited SiOx on plasma-enhanced chemical vapor-deposition (PECVD) SiNx films, effectively protected the TFT active region from plasma damage and minimized changes in the chemical composition of the semiconductor layer. A dual-dielectric PECVD SiOx/PECVD SiNx gate-dielectric, using SiOx as a barrier layer, also effectively prevented out-diffusion of hydrogen atoms from the PECVD SiNx-gate dielectric to the IGZO channel layer during the device fabrication.

Two-bit multi-level phase change random access memory with a triple phase change material stack structure

NASA Astrophysics Data System (ADS)

Gyanathan, Ashvini; Yeo, Yee-Chia

2012-11-01

This work demonstrates a novel two-bit multi-level device structure comprising three phase change material (PCM) layers, separated by SiN thermal barrier layers. This triple PCM stack consisted of (from bottom to top), Ge2Sb2Te5 (GST), an ultrathin SiN barrier, nitrogen-doped GST, another ultrathin SiN barrier, and Ag0.5In0.5Sb3Te6. The PCM layers can selectively amorphize to form 4 different resistance levels ("00," "01," "10," and "11") using respective voltage pulses. Electrical characterization was extensively performed on these devices. Thermal analysis was also done to understand the physics behind the phase changing characteristics of the two-bit memory devices. The melting and crystallization temperatures of the PCMs play important roles in the power consumption of the multi-level devices. The electrical resistivities and thermal conductivities of the PCMs and the SiN thermal barrier are also crucial factors contributing to the phase changing behaviour of the PCMs in the two-bit multi-level PCRAM device.

Quantification of the effects of environmental leaching factors on emissions from bottom ash in road construction.

PubMed

Ecke, Holger; Aberg, Annika

2006-06-01

The re-use of bottom ash in road construction necessitates a tool to predict the impact of trace metals on the surroundings over the lifetime of the road. The aim of this work was to quantify the effect of environmental factors that are supposed to influence leaching, so as to suggest guidelines in developing a leaching procedure for the testing of incineration residues re-used in road constructions. The effects of pH, L/S (liquid-to-solid ratio), leaching time, and leaching atmosphere on the leachate concentrations of Cd, Cr, Cu, Ni, Pb, and Zn were studied using a two-level full factorial design. The most significant factor for all responses was the pH, followed by L/S, though the importance of pH and L/S is often ignored in leaching tests. Multiple linear regression models describing the variation in leaching data had R(2) values ranging from 61-97%. A two-step pH-stat leaching procedure that considers pH as well as L/S and leaching time was suggested.

Programmable DNA tile self-assembly using a hierarchical sub-tile strategy.

PubMed

Shi, Xiaolong; Lu, Wei; Wang, Zhiyu; Pan, Linqiang; Cui, Guangzhao; Xu, Jin; LaBean, Thomas H

2014-02-21

DNA tile based self-assembly provides a bottom-up approach to construct desired nanostructures. DNA tiles have been directly constructed from ssDNA and readily self-assembled into 2D lattices and 3D superstructures. However, for more complex lattice designs including algorithmic assemblies requiring larger tile sets, a more modular approach could prove useful. This paper reports a new DNA 'sub-tile' strategy to easily create whole families of programmable tiles. Here, we demonstrate the stability and flexibility of our sub-tile structures by constructing 3-, 4- and 6-arm DNA tiles that are subsequently assembled into 2D lattices and 3D nanotubes according to a hierarchical design. Assembly of sub-tiles, tiles, and superstructures was analyzed using polyacrylamide gel electrophoresis and atomic force microscopy. DNA tile self-assembly methods provide a bottom-up approach to create desired nanostructures; the sub-tile strategy adds a useful new layer to this technique. Complex units can be made from simple parts. The sub-tile approach enables the rapid redesign and prototyping of complex DNA tile sets and tiles with asymmetric designs.

Green Building and School Construction.

ERIC Educational Resources Information Center

DiNola, Ralph; Guerra, Jerry

2002-01-01

Discusses the benefits of green, or high-performance, buildings, such as health and comfort, cost effectiveness, and sustainability. Explores the barriers to their use by schools--most notably cost. Offers suggestions on overcoming these barriers. (EV)

Importance of Macrophyte Quality in Determining Life-History Traits of the Apple Snails Pomacea canaliculata: Implications for Bottom-Up Management of an Invasive Herbivorous Pest in Constructed Wetlands

PubMed Central

Yam, Rita S. W.; Fan, Yen-Tzu; Wang, Tzu-Ting

2016-01-01

Pomacea canaliculata (Ampullariidae) has extensively invaded most Asian constructed wetlands and its massive herbivory of macrophytes has become a major cause of ecosystem dysfunctioning of these restored habitats. We conducted non-choice laboratory feeding experiments of P. canaliculata using five common macrophyte species in constructed wetlands including Ipomoea aquatica, Commelina communis, Nymphoides coreana, Acorus calamus and Phragmites australis. Effects of macrophytes on snail feeding, growth and fecundity responses were evaluated. Results indicated that P. canaliculata reared on Ipomoea had the highest feeding and growth rates with highest reproductive output, but all individuals fed with Phragmites showed lowest feeding rates and little growth with poorest reproductive output. Plant N and P contents were important for enhancing palatability, supporting growth and offspring quantity of P. canaliculata, whilst toughness, cellulose and phenolics had critically deterrent effects on various life-history traits. Although snail offspring quality was generally consistent regardless of maternal feeding conditions, the reduced growth and offspring quantity of the poorly-fed snails in constructed wetlands dominated by the less-palatable macrophytes could limit the invasive success of P. canaliculata. Effective bottom-up control of P. canaliculata in constructed wetlands should involve selective planting strategy using macrophytes with low nutrient and high toughness, cellulose and phenolic contents. PMID:26927135

Causality in Psychiatry: A Hybrid Symptom Network Construct Model

PubMed Central

Young, Gerald

2015-01-01

Causality or etiology in psychiatry is marked by standard biomedical, reductionistic models (symptoms reflect the construct involved) that inform approaches to nosology, or classification, such as in the DSM-5 [Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition; (1)]. However, network approaches to symptom interaction [i.e., symptoms are formative of the construct; e.g., (2), for posttraumatic stress disorder (PTSD)] are being developed that speak to bottom-up processes in mental disorder, in contrast to the typical top-down psychological construct approach. The present article presents a hybrid top-down, bottom-up model of the relationship between symptoms and mental disorder, viewing symptom expression and their causal complex as a reciprocally dynamic system with multiple levels, from lower-order symptoms in interaction to higher-order constructs affecting them. The hybrid model hinges on good understanding of systems theory in which it is embedded, so that the article reviews in depth non-linear dynamical systems theory (NLDST). The article applies the concept of emergent circular causality (3) to symptom development, as well. Conclusions consider that symptoms vary over several dimensions, including: subjectivity; objectivity; conscious motivation effort; and unconscious influences, and the degree to which individual (e.g., meaning) and universal (e.g., causal) processes are involved. The opposition between science and skepticism is a complex one that the article addresses in final comments. PMID:26635639

Importance of Macrophyte Quality in Determining Life-History Traits of the Apple Snails Pomacea canaliculata: Implications for Bottom-Up Management of an Invasive Herbivorous Pest in Constructed Wetlands.

PubMed

Yam, Rita S W; Fan, Yen-Tzu; Wang, Tzu-Ting

2016-02-24

Pomacea canaliculata (Ampullariidae) has extensively invaded most Asian constructed wetlands and its massive herbivory of macrophytes has become a major cause of ecosystem dysfunctioning of these restored habitats. We conducted non-choice laboratory feeding experiments of P. canaliculata using five common macrophyte species in constructed wetlands including Ipomoea aquatica, Commelina communis, Nymphoides coreana, Acorus calamus and Phragmites australis. Effects of macrophytes on snail feeding, growth and fecundity responses were evaluated. Results indicated that P. canaliculata reared on Ipomoea had the highest feeding and growth rates with highest reproductive output, but all individuals fed with Phragmites showed lowest feeding rates and little growth with poorest reproductive output. Plant N and P contents were important for enhancing palatability, supporting growth and offspring quantity of P. canaliculata, whilst toughness, cellulose and phenolics had critically deterrent effects on various life-history traits. Although snail offspring quality was generally consistent regardless of maternal feeding conditions, the reduced growth and offspring quantity of the poorly-fed snails in constructed wetlands dominated by the less-palatable macrophytes could limit the invasive success of P. canaliculata. Effective bottom-up control of P. canaliculata in constructed wetlands should involve selective planting strategy using macrophytes with low nutrient and high toughness, cellulose and phenolic contents.

Series interconnected photovoltaic cells and method for making same

DOEpatents

Albright, Scot P.; Chamberlin, Rhodes R.; Thompson, Roger A.

1995-01-01

A novel photovoltaic module (10) and method for constructing the same are disclosed. The module (10) includes a plurality of photovoltaic cells (12) formed on a substrate (14) and laterally separated by interconnection regions (15). Each cell (12) includes a bottom electrode (16), a photoactive layer (18) and a top electrode layer (20). Adjacent cells (12) are connected in electrical series by way of a conductive-buffer line (22). The buffer line (22) is also useful in protecting the bottom electrode (16) against severing during downstream layer cutting processes.

Engineering and characterization of aluminum oxide-based Magnetic Tunnel Junctions

NASA Astrophysics Data System (ADS)

Ji, Chengxiang

Magnetic Tunnel Junctions (MTJs) consisting of two ferromagnetic layers separated by an insulator layer have attracted great interest due to their applications in magnetic read heads and potential applications in magnetic random access memory. Materials science plays an important role in the performance of the MTJs. The goal of this research was to focus on how the materials properties affect the tunneling magnetoresistance (TMR) of AlOx-based MTJs with (Co, Fe) electrodes. A method was developed to fabricate epitaxial (Co, Fe) (001) thin films on Si substrates using TiN buffer and a novel processing technique in order to achieve smooth interfaces between the electrode and the AlOx tunnel barrier. The (Co, Fe) thin films with other orientations, i.e. (110) and (211), were also grown on TiN buffered substrates of Si (111) and (011). Numerous MTJs with epitaxial bottom electrode were fabricated to investigate the effect of the materials properties of the (Co, Fe) electrode on the TMR of these junctions. A strain induced TMR enhancement was discovered, where the trend of increasing TMR of the MTJs is the same as that of the strain of the bottom electrode. The strain was originated from the lattice mismatch between (Co, Fe) electrode and the buffer layers in the MTJs, which will vary with annealing temperatures. Since the interface roughness and the barrier properties were the same within the uncertainties of the measurement, this TMR enhancement was attributed to the presence of strain. The TMR values were also compared for MTJs with the bottom electrode in the (001), (110) and (211) orientations. The anisotropic property of (Co, Fe) was confirmed and the (001) orientation has larger spin polarization than the (110) and (211) orientations. By careful manipulation of the bottom electrode, including strain, roughness and orientation, 77% TMR was obtained for AlOx-based MTJs. The phase transformation of Pt0.5-xMn0.5+x from fcc to Ll0 was investigated. The experimental results showed the onset temperature for phase transformation increase as the composition deviates from stoichiometry but slows down the kinetics of transformation.

Trench Safety–Using a Qualitative Approach to Understand Barriers and Develop Strategies to Improve Trenching Practices

PubMed Central

FLYNN, MICHAEL A.; SAMPSON, JULIE M.

2015-01-01

Despite efforts to ensure workplace safety and health, injuries and fatalities related to trenching and excavation remain alarmingly high in the construction industry. Because properly installed trenching protective systems can potentially reduce the significant number of trenching fatalities, there is clearly a need to identify the barriers to the use of these systems and to develop strategies to ensure these systems are utilized consistently. The current study reports on the results of focus groups with construction workers and safety management personnel to better understand these barriers and to identify solutions. The results suggest several factors, from poor planning to pressures from experienced workers and supervisors, which present barriers to safe trenching practices. Based on the results, it is recommended that safety trainings incorporate unique messages for new workers, experienced workers and management in an effort to motivate each group to work safely as well as provide them with solutions to overcome the identified barriers. PMID:26550006

Building Information Modelling: Challenges and Barriers in Implement of BIM for Interior Design Industry in Malaysia

NASA Astrophysics Data System (ADS)

Hamid, A. B. Abd; Taib, M. Z. Mohd; Razak, A. H. N. Abdul; Embi, M. R.

2018-04-01

Building Information Modelling (BIM) is an innovative approach that has developed crossways the global in architecture, engineering and construction (AEC) industry. The construction industry of Malaysia has undergone a rapid development and dynamic technology adoption in advance and methods between the players industry and stakeholders. Consequently, limited technologies and devices have not been successful as it should have been. This study will be emphasizing scenarios of challenges and barriers in adopting BIM in interior design industry in Malaysia. The study was emphasizing the challenges and barriers in BIM usage from the designer’s perspective. The data are collected through the questionnaires as to identifying the barriers, knowledge, readiness and awareness and distributed to interior design firms were selected randomly. The finding of this research is to examine the barriers and causes of variables BIM usage for interior design industry in Malaysia. The outcome of this study is to identify the constraint of adoption BIM in interior design industry compare to others players in same industry.

Saltwater-barrier line in Florida : concepts, considerations, and site examples

USGS Publications Warehouse

Hughes, Jerry L.

1979-01-01

Construction of canals and enlargement of streams in Florida has been mostly to alleviate impact of floods and to drain wetlands for development. Land drainage and heavy pumpage from coastal water-table aquifers has degraded potable ground and surface water with saltwater. Control of saltwater intrusion is possible through implementation of certain hydrologic principles. State of Florida statute 373.033 provides for a saltwater-barrier line in areas of saltwater intrusion along canals. A saltwater-barrier line is defined as the allowable landward limit that a canal shall be constructed or enlarged or a stream deepened or enlarged without a salinity-control structure seaward of the saltwater-barrier line. The salinity control structure controls saltwater intrusion along a surface-water channel and assists in controlling saltwater intrusion into shallow aquifers. This report briefly reviews the fundamentals of saltwater intrusion in surface-water channels and associated coastal aquifers, describes the effects of established saltwater-barrier lines in Florida, and gives a history of the use and benefits of salinity-control structures. (Woodard-USGS).

Use of municipal solid waste incineration bottom ashes in alkali-activated materials, ceramics and granular applications: A review.

PubMed

Silva, R V; de Brito, J; Lynn, C J; Dhir, R K

2017-10-01

This paper presents a literature review on the incorporation of municipal solid waste incinerated bottom ash as raw material in several markets, other than those where it is conventionally used, such as geotechnical applications and road pavement construction. The main findings of an ample selection of experimental investigations on the use of the bottom ash as precursor of alkali-activated materials, as an adsorbent material for the removal of hazardous elements from wastewater and landfill gases, as soil replacement in agricultural activities, as partial or complete substitute of raw materials for the manufacture of ceramic-based products, as landfill cover and as biogas production enhancer, were gathered, collated and analysed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Root causes occurrence of low BIM adoption in Malaysia: System dynamics modelling approach

NASA Astrophysics Data System (ADS)

Mamter, Shahela; Aziz, Abdul Rashid Abdul; Zulkepli, Jafri

2017-11-01

The global implementation of BIM in the construction field is increasing worldwide. Due to the advantages offered by BIM, its implementation is considered important in the construction projects. Nevertheless, the Construction Industry Transformation Plan has reported that the adoption of Building Information Modelling (BIM) in Malaysia is still low and it is estimated at only 10 percent adoption amongst construction stake players. The barriers influencing the occurrence of low adoption BIM in Malaysia have been studied by some researchers. However, these researchers did not investigate the root causes which might lead to the recurring of the barriers to BIM adoption. Root causes that immediately occurrence of barriers, also known as precipitants or trigger causes. This conceptual paper developed the causal loop diagram (CLD) which presents the relationship between the perceived variables using system dynamic modelling approach. The findings revealed a novelty validated diagrams that design the holistic dynamic relationship on the root causes occurrence of low BIM adoption. Nonetheless, the diagram subject to more empirical testing for its practicability and further refinement upon more results expected to emerge as the research progresses.

Data exploration of social client relationship management (CRM 2.0) adoption in the Nigerian construction business.

PubMed

Ojelabi, Rapheal A; Afolabi, Adedeji O; Oyeyipo, Opeyemi O; Tunji-Olayeni, Patience F; Adewale, Bukola A

2018-06-01

Integrating social client relationship management (CRM 2.0) in the built environment can enhance the relationship between construction organizations and client towards sustaining a long and lasting collaboration. The data exploration analyzed the e-readiness of contracting and consulting construction firms in the uptake of CRM 2.0 and the barriers encountered in the adoption of the modern business tool. The targeted organizations consist of seventy five (75) construction businesses operating in Lagos State which were selected from a pool of registered contracting and consulting construction firms using random sampling technique. Descriptive statistics of the e-readiness of contracting and consulting construction firms for CRM 2.0 adoption and barriers limiting its uptake were analyzed. Also, inferential analysis using Mann-Whitney U statistical and independent sample t-test was performed on the dataset obtained. The data generated will support construction firms on the necessity to engage in client social relationship management in ensuring sustainable client relationship management in the built environment.

Reverse logistics in the construction industry.

PubMed

Hosseini, M Reza; Rameezdeen, Raufdeen; Chileshe, Nicholas; Lehmann, Steffen

2015-06-01

Reverse logistics in construction refers to the movement of products and materials from salvaged buildings to a new construction site. While there is a plethora of studies looking at various aspects of the reverse logistics chain, there is no systematic review of literature on this important subject as applied to the construction industry. Therefore, the objective of this study is to integrate the fragmented body of knowledge on reverse logistics in construction, with the aim of promoting the concept among industry stakeholders and the wider construction community. Through a qualitative meta-analysis, the study synthesises the findings of previous studies and presents some actions needed by industry stakeholders to promote this concept within the real-life context. First, the trend of research and terminology related with reverse logistics is introduced. Second, it unearths the main advantages and barriers of reverse logistics in construction while providing some suggestions to harness the advantages and mitigate these barriers. Finally, it provides a future research direction based on the review. © The Author(s) 2015.

Oxygen cocoon for patients under intensive care

NASA Technical Reports Server (NTRS)

Maas, J. W.

1975-01-01

Cocoon is made from Teflon film. It includes full-length, pressure zipper on top side and bottom part is rigid pad constructed of burn-resistant material. Cocoon includes oxygen supply port with exhaust port at opposite end.

49 CFR 178.915 - General Large Packaging standards.

Code of Federal Regulations, 2012 CFR

2012-10-01

... intended for solid hazardous materials must be sift-proof and water-resistant. (b) All service equipment... times. (e) Large Packaging design types must be constructed in such a way as to be bottom-lifted or top...

49 CFR 178.915 - General Large Packaging standards.

Code of Federal Regulations, 2013 CFR

2013-10-01

... intended for solid hazardous materials must be sift-proof and water-resistant. (b) All service equipment... times. (e) Large Packaging design types must be constructed in such a way as to be bottom-lifted or top...

49 CFR 178.915 - General Large Packaging standards.

Code of Federal Regulations, 2014 CFR

2014-10-01

... intended for solid hazardous materials must be sift-proof and water-resistant. (b) All service equipment... times. (e) Large Packaging design types must be constructed in such a way as to be bottom-lifted or top...

Evaluating the use of waste-to-energy bottom ash as road construction materials.

DOT National Transportation Integrated Search

2014-02-01

Current management practice, existing regulations, and environmental consequences of municipal solid : waste incineration (MSWI) ash utilization were comprehensively reviewed worldwide and nationwide : in the U.S. Efforts were made to physically and ...

Hog-ringer speeds seed trap construction

Treesearch

D.O. Hall

1964-01-01

An upholsterer's hog-ringer, with Hill's No. 1 pig rings, increased production of one-foot-square wire seed traps by 25 percent. A design modification allowed two bottom sections to be cut from a 36-inch roll of wire.

Thermal Analysis of Reinforced Concrete Tank for Conditioning Wood by FEM Method

NASA Astrophysics Data System (ADS)

Błaszczyński, Tomasz; Babiak, Michał; Wielentejczyk, Przemysław

2017-10-01

The article introduces the analysis of a RC tank for conditioning wood carried out using the FEM (Finite Element Method). A temperature gradient distribution increase resulting from the influence of hot liquid filling the tank was defined. Values of gradients in border sections of the tank walls and the bottom were defined on the basis of the isotherm method. The obtained results were compared with empirical formulas from literature. Strength analyses were also carried out. Additionally, the problematic aspects of elongated monolithic tanks for liquids were introduced, especially regarding large temperature gradients and the means of necessary technical solutions. The use of the FEM method for designing engineering objects is, nowadays, an irreplaceable solution. In the case of the discussed tank, a spatial model of the construction mapping its actual performance was constructed in order to correctly estimate the necessary dimensions of wall and bottom sections, as well as reinforcement.

Bottom-up construction of a superstructure in a porous uranium-organic crystal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Peng; Vermeulen, Nicolaas A.; Malliakas, Christos D.

Bottom-up construction of highly intricate structures from simple building blocks remains one of the most difficult challenges in chemistry. We report a structurally complex, mesoporous uranium-based metal-organic framework (MOF) made from simple starting components. The structure comprises 10 uranium nodes and seven tricarboxylate ligands (both crystallographically nonequivalent), resulting in a 173.3-angstrom cubic unit cell enclosing 816 uranium nodes and 816 organic linkers—the largest unit cell found to date for any nonbiological material. The cuboctahedra organize into pentagonal and hexagonal prismatic secondary structures, which then form tetrahedral and diamond quaternary topologies with unprecedented complexity. This packing results in the formation ofmore » colossal icosidodecahedral and rectified hexakaidecahedral cavities with internal diameters of 5.0 nanometers and 6.2 nanometers, respectively—ultimately giving rise to the lowest-density MOF reported to date.« less

Optimized capping layers for EUV multilayers

DOEpatents

Bajt, Sasa [Livermore, CA; Folta, James A [Livermore, CA; Spiller, Eberhard A [Livermore, CA

2004-08-24

A new capping multilayer structure for EUV-reflective Mo/Si multilayers consists of two layers: A top layer that protects the multilayer structure from the environment and a bottom layer that acts as a diffusion barrier between the top layer and the structure beneath. One embodiment combines a first layer of Ru with a second layer of B.sub.4 C. Another embodiment combines a first layer of Ru with a second layer of Mo. These embodiments have the additional advantage that the reflectivity is also enhanced. Ru has the best oxidation resistance of all materials investigated so far. B.sub.4 C is an excellent barrier against silicide formation while the silicide layer formed at the Si boundary is well controlled.

46 CFR 38.05-1 - Design and construction of vessels-general-TB/ALL.

Code of Federal Regulations, 2010 CFR

2010-10-01

... system shall satisfy the requirements for toughness specified in subchapter F (Marine Engineering) of... secondary barrier is required, the material of that barrier and of contiguous hull structure shall have...

Systematic Review of Methods in Low-Consensus Fields: Supporting Commensuration through `Construct-Centered Methods Aggregation' in the Case of Climate Change Vulnerability Research.

PubMed

Delaney, Aogán; Tamás, Peter A; Crane, Todd A; Chesterman, Sabrina

2016-01-01

There is increasing interest in using systematic review to synthesize evidence on the social and environmental effects of and adaptations to climate change. Use of systematic review for evidence in this field is complicated by the heterogeneity of methods used and by uneven reporting. In order to facilitate synthesis of results and design of subsequent research a method, construct-centered methods aggregation, was designed to 1) provide a transparent, valid and reliable description of research methods, 2) support comparability of primary studies and 3) contribute to a shared empirical basis for improving research practice. Rather than taking research reports at face value, research designs are reviewed through inductive analysis. This involves bottom-up identification of constructs, definitions and operationalizations; assessment of concepts' commensurability through comparison of definitions; identification of theoretical frameworks through patterns of construct use; and integration of transparently reported and valid operationalizations into ideal-type research frameworks. Through the integration of reliable bottom-up inductive coding from operationalizations and top-down coding driven from stated theory with expert interpretation, construct-centered methods aggregation enabled both resolution of heterogeneity within identically named constructs and merging of differently labeled but identical constructs. These two processes allowed transparent, rigorous and contextually sensitive synthesis of the research presented in an uneven set of reports undertaken in a heterogenous field. If adopted more broadly, construct-centered methods aggregation may contribute to the emergence of a valid, empirically-grounded description of methods used in primary research. These descriptions may function as a set of expectations that improves the transparency of reporting and as an evolving comprehensive framework that supports both interpretation of existing and design of future research.

Systematic Review of Methods in Low-Consensus Fields: Supporting Commensuration through `Construct-Centered Methods Aggregation’ in the Case of Climate Change Vulnerability Research

PubMed Central

Crane, Todd A.; Chesterman, Sabrina

2016-01-01

There is increasing interest in using systematic review to synthesize evidence on the social and environmental effects of and adaptations to climate change. Use of systematic review for evidence in this field is complicated by the heterogeneity of methods used and by uneven reporting. In order to facilitate synthesis of results and design of subsequent research a method, construct-centered methods aggregation, was designed to 1) provide a transparent, valid and reliable description of research methods, 2) support comparability of primary studies and 3) contribute to a shared empirical basis for improving research practice. Rather than taking research reports at face value, research designs are reviewed through inductive analysis. This involves bottom-up identification of constructs, definitions and operationalizations; assessment of concepts’ commensurability through comparison of definitions; identification of theoretical frameworks through patterns of construct use; and integration of transparently reported and valid operationalizations into ideal-type research frameworks. Through the integration of reliable bottom-up inductive coding from operationalizations and top-down coding driven from stated theory with expert interpretation, construct-centered methods aggregation enabled both resolution of heterogeneity within identically named constructs and merging of differently labeled but identical constructs. These two processes allowed transparent, rigorous and contextually sensitive synthesis of the research presented in an uneven set of reports undertaken in a heterogenous field. If adopted more broadly, construct-centered methods aggregation may contribute to the emergence of a valid, empirically-grounded description of methods used in primary research. These descriptions may function as a set of expectations that improves the transparency of reporting and as an evolving comprehensive framework that supports both interpretation of existing and design of future research. PMID:26901409

24 CFR 3280.502 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-04-01

... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Thermal Protection § 3280.502 Definitions. (a... air barrier surrounding the living space which serves to limit air leakage. In construction using...

Barriers and Supports for Continuing in Mathematics and Science: Gender and Educational Level Differences

ERIC Educational Resources Information Center

Fouad, Nadya A.; Hackett, Gail; Smith, Philip L.; Kantamneni, Neeta; Fitzpatrick, Mary; Haag, Susan; Spencer, Dee

2010-01-01

This article presents three studies that provide an in-depth examination of STEM-related supports and barriers. These studies constructed an instrument to identify male and female perceptions of the barriers and supports for pursuing coursework and/or careers in mathematics and sciences domains; to pilot test and refine that instrument; and then…

Procedural uncertainties of Proctor compaction tests applied on MSWI bottom ash.

PubMed

Izquierdo, Maria; Querol, Xavier; Vazquez, Enric

2011-02-28

MSWI bottom ash is a well-graded highly compactable material that can be used as a road material in unbound pavements. Achieving the compactness assumed in the design of the pavement is of primary concern to ensure long term structural stability. Regulations on road construction in a number of EU countries rely on standard tests originally developed for natural aggregates, which may not be appropriate to accurately assess MSWI bottom ash. This study is intended to assist in consistently assessing MSWI bottom ash compaction by means of the Proctor method. This test is routinely applied to address unbound road materials and suggests two methods. Compaction parameters show a marked procedural dependency due to the particle morphology and weak particle strength of ash. Re-compacting a single batch sample to determine Proctor curves is a common practise that turns out to overvalue optimum moisture contents and maximum dry densities. This could result in wet-side compactions not meeting stiffness requirements. Inaccurate moisture content measurements during testing may also induce erroneous determinations of compaction parameters. The role of a number of physical properties of MSWI bottom ash in compaction is also investigated. Copyright © 2011 Elsevier B.V. All rights reserved.

Bottom Topographic Changes of Poyang Lake During Past Decade Using Multi-temporal Satellite Images

NASA Astrophysics Data System (ADS)

Zhang, S.

2015-12-01

Poyang Lake, as a well-known international wetland in the Ramsar Convention List, is the largest freshwater lake in China. It plays crucial ecological role in flood storage and biological diversity. Poyang Lake is facing increasingly serious water crises, including seasonal dry-up, decreased wetland area, and water resource shortage, all of which are closely related to progressive bottom topographic changes over recent years. Time-series of bottom topography would contribute to our understanding of the lake's evolution during the past several decades. However, commonly used methods for mapping bottom topography fail to frequently update quality bathymetric data for Poyang Lake restricted by weather and accessibility. These deficiencies have limited our ability to characterize the bottom topographic changes and understanding lake erosion or deposition trend. To fill the gap, we construct a decadal bottom topography of Poyang Lake with a total of 146 time series medium resolution satellite images based on the Waterline Method. It was found that Poyang Lake has eroded with a rate of -14.4 cm/ yr from 2000 to 2010. The erosion trend was attributed to the impacts of human activities, especially the operation of the Three Gorge Dams, sand excavation, and the implementation of water conservancy project. A decadal quantitative understanding bottom topography of Poyang Lake might provide a foundation to model the lake evolutionary processes and assist both researchers and local policymakers in ecological management, wetland protection and lake navigation safety.

Feasible experimental study on the utilization of a 300 MW CFB boiler desulfurizating bottom ash for construction applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, X.F.; Amano, R.S.

2006-12-15

CFB boiler ash cannot be used as a cement replacement in concrete due to its unacceptably high sulfur content. The disposal in landfills has been the most common means of handling ash in circulating fluidized bed boiler power plants. However for a 300 MW CFB boiler power plant, there will be 600,000 tons of ash discharged per year and will result in great volumes and disposal cost of ash byproduct. It was very necessary to solve the utilization of CFB ash and to decrease the disposal cost of CFB ash. The feasible experimental study results on the utilization of themore » bottom ashes of a 300 MW CFB boiler in Baima power plant in China were reported in this paper. The bottom ashes used for test came from the discharged bottom ashes in a 100 MW CFB boiler in which the anthracite and limestone designed for the 300 MW CFB project was burned. The results of this study showed that the bottom ash could be used for cementitious material, road concrete, and road base material. The masonry cements, road concrete with 30 MPa compressive strength and 4.0 MPa flexural strength, and the road base material used for base courses of the expressway, the main road and the minor lane were all prepared with milled CFB bottom ashes in the lab. The better methods of utilization of the bottom ashes were discussed in this paper.« less

Environmental assessment of incinerator residue utilisation.

PubMed

Toller, S; Kärrman, E; Gustafsson, J P; Magnusson, Y

2009-07-01

Incineration ashes may be treated either as a waste to be dumped in landfill, or as a resource that is suitable for re-use. In order to choose the best management scenario, knowledge is needed on the potential environmental impact that may be expected, including not only local, but also regional and global impact. In this study, A life cycle assessment (LCA) based approach was outlined for environmental assessment of incinerator residue utilisation, in which leaching of trace elements as well as other emissions to air and water and the use of resources were regarded as constituting the potential environmental impact from the system studied. Case studies were performed for two selected ash types, bottom ash from municipal solid waste incineration (MSWI) and wood fly ash. The MSWI bottom ash was assumed to be suitable for road construction or as drainage material in landfill, whereas the wood fly ash was assumed to be suitable for road construction or as a nutrient resource to be recycled on forest land after biofuel harvesting. Different types of potential environmental impact predominated in the activities of the system and the use of natural resources and the trace element leaching were identified as being relatively important for the scenarios compared. The scenarios differed in use of resources and energy, whereas there is a potential for trace element leaching regardless of how the material is managed. Utilising MSWI bottom ash in road construction and recycling of wood ash on forest land saved more natural resources and energy than when these materials were managed according to the other scenarios investigated, including dumping in landfill.

What Works to Reduce Unnecessary Care for Bronchiolitis? A Qualitative Analysis of a National Collaborative.

PubMed

Ralston, Shawn L; Atwood, Emily Carson; Garber, Matthew D; Holmes, Alison Volpe

2017-03-01

Unnecessary care is well established as a quality problem affecting acute viral bronchiolitis, one of the most common pediatric illnesses. Although there is an extensive quality improvement literature on the disease, published work primarily reflects the experience of freestanding children's hospitals. We sought to better understand the specific barriers and drivers for successful quality improvement in community and nonfreestanding children's facilities. We undertook a mixed methods study to identify correlates of success in a bronchiolitis quality improvement collaborative of community hospitals and children's hospitals within adult hospitals. We assessed site demographic characteristics, compliance with project interventions, and team engagement for association with end of project performance. We then used performance quartiles on a composite assessment of project measures (use of bronchodilators and steroids) to design a purposive sample of sites approached for qualitative interviews. Team engagement was the only factor quantitatively associated with better performance in the overall cohort. Fifteen sites, from the total cohort of 21, completed qualitative interviews. Qualitative themes around team engagement, including the presence of buy-in for successful sites and the inability to engage colleagues at unsuccessful sites, were important differentiating factors between top and bottom performance quartiles. Regardless of performance quartile, most programs cited intrainstitutional competition for limited resources to do quality improvement work as a specific barrier for pediatrics. The ability to overcome such barriers and specifically garner information technology (IT) resources also differentiated the top and bottom performance quartiles. Team engagement showed a consistent association with success across our quantitative and qualitative evaluations. Competition for limited resources in this cohort of nonfreestanding children's programs, particularly those in hospital IT, was a key qualitative theme. Copyright © 2016 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

Navigation Effects on Asian Carp Movement Past Electric Barrier, Chicago Sanitary and Ship Canal

DTIC Science & Technology

2016-02-01

model was necessary to better address the potential mechanisms for transport of Asian carp. In addition to primarily modeling stunned fish , this...model fish positions that varied within the water column to include bottom, near-surface, and mid-depth placement. As additional information was...in the image represents an identified model fish . In addition , fish could be tracked from one frame to the next frame to calculate their velocity

Closing the Gap: A Report on the Wingspread Conference "Beyond the Standards Horse Race: Implementation, Assessment, and Accountability--the Keys to Improving Student Achievement" (Racine, Wisconsin, November 2-4, 1999). Special Report.

ERIC Educational Resources Information Center

Duggan, Terri, Ed.; Holmes, Madelyn, Ed.

This report highlights results from the 1999 Wingspread Conference on improving student achievement, a gathering of educators, leaders, and policymakers that opened a dialogue about barriers to full implementation of high standards for all students. Participants discussed five papers that examined these issues from top to bottom--from the…

Crushable barrier blocks installed : research notes.

DOT National Transportation Integrated Search

1997-09-01

The Oregon Department of Transportation : is testing another low cost life : saving device. On September 9, 1997, : an ADIEM II concrete barrier end : terminal was installed on I-5 south of : Salem, at the Delaney Road : overcrossing construction pro...

49 CFR 178.704 - General IBC standards.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., deterioration due to exposure to the external environment. IBCs intended for solid hazardous materials must be... must be constructed in such a way as to be bottom-lifted or top-lifted as specified in §§ 178.811 and...

49 CFR 178.704 - General IBC standards.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., deterioration due to exposure to the external environment. IBCs intended for solid hazardous materials must be... must be constructed in such a way as to be bottom-lifted or top-lifted as specified in §§ 178.811 and...

Developing a questionnaire to identify perceived barriers for implementing the Dutch physical therapy COPD clinical practice guideline.

PubMed

van der Wees, Philip J; Zagers, Cor A M; de Die, Sara E; Hendriks, Erik J M; Nijhuis-van der Sanden, Maria W G; de Bie, Rob A

2013-05-01

Clinical practice guidelines have been developed to assist healthcare practitioners in clinical decision making. Publication of clinical practice guidelines does not automatically lead to their uptake and barrier identification has been recognized as an important step in implementation planning. This study aimed at developing a questionnaire to identify perceived barriers for implementing the Dutch COPD guideline for physical therapists and its recommended measurement instruments. An overall questionnaire, based on two existing questionnaires, was constructed to identify barriers and facilitators for implementing the COPD guideline. The construct of the questionnaire was assessed in a cross-sectional study among 246 chest physical therapists. Factor analysis was conducted to explore underlying dimensions. Psychometric properties were analyzed using Cronbach's alpha. Barriers and facilitators were assessed using descriptive statistics. Some 139 physical therapists (57%) responded. Factor analysis revealed 4-factor and 5-factor solutions with an explained variance of 36% and 39% respectively. Cronbach's alpha of the overall questionnaire was 0.90, and varied from 0.66 to 0.92 for the different factors. Underlying domains of the 5-factor solution were characterized as: attitude towards using measurement instruments, knowledge and skills of the physical therapist, applicability of the COPD guideline, required investment of time & money, and patient characteristics. Physical therapists showed a positive attitude toward using the COPD guideline. Main barriers for implementation were required time investment and financial constraints. The construct of the questionnaire revealed relevant underlying domains for the identification of barriers and facilitators for implementing the COPD guideline. The questionnaire allowed for tailoring to the target group and may be used across health care professionals as basis for in-depth analysis of barriers to specific recommendations in guidelines. The results of the questionnaire alone do not provide sufficient information to inform the development of an implementation strategy. The infrastructure for developing the guideline can be used for addressing key barriers by the guideline development group, using the questionnaire as well as in-depth analysis such as focus group interviews. Further development of methods for prospective identification of barriers and consequent tailoring of implementation interventions is required.

Developing a questionnaire to identify perceived barriers for implementing the Dutch physical therapy COPD clinical practice guideline

PubMed Central

2013-01-01

Background Clinical practice guidelines have been developed to assist healthcare practitioners in clinical decision making. Publication of clinical practice guidelines does not automatically lead to their uptake and barrier identification has been recognized as an important step in implementation planning. This study aimed at developing a questionnaire to identify perceived barriers for implementing the Dutch COPD guideline for physical therapists and its recommended measurement instruments. Methods An overall questionnaire, based on two existing questionnaires, was constructed to identify barriers and facilitators for implementing the COPD guideline. The construct of the questionnaire was assessed in a cross-sectional study among 246 chest physical therapists. Factor analysis was conducted to explore underlying dimensions. Psychometric properties were analyzed using Cronbach’s alpha. Barriers and facilitators were assessed using descriptive statistics. Results Some 139 physical therapists (57%) responded. Factor analysis revealed 4-factor and 5-factor solutions with an explained variance of 36% and 39% respectively. Cronbach’s alpha of the overall questionnaire was 0.90, and varied from 0.66 to 0.92 for the different factors. Underlying domains of the 5-factor solution were characterized as: attitude towards using measurement instruments, knowledge and skills of the physical therapist, applicability of the COPD guideline, required investment of time & money, and patient characteristics. Physical therapists showed a positive attitude toward using the COPD guideline. Main barriers for implementation were required time investment and financial constraints. Conclusions The construct of the questionnaire revealed relevant underlying domains for the identification of barriers and facilitators for implementing the COPD guideline. The questionnaire allowed for tailoring to the target group and may be used across health care professionals as basis for in-depth analysis of barriers to specific recommendations in guidelines. The results of the questionnaire alone do not provide sufficient information to inform the development of an implementation strategy. The infrastructure for developing the guideline can be used for addressing key barriers by the guideline development group, using the questionnaire as well as in-depth analysis such as focus group interviews. Further development of methods for prospective identification of barriers and consequent tailoring of implementation interventions is required. PMID:23631555

Mathematical modelling for distribution of heavy metals in estuary area of Red River (Vietnam)

NASA Astrophysics Data System (ADS)

Nguyen, N. T. T.; Volkova, I. V.

2018-05-01

In this paper, the authors studied the features of spatial distribution of some heavy metals (Pb, Hg, As) in the system “suspended substance - bottom sediments” in the mouth area of the Red River (Vietnam). A mathematical modelling for diffusion processes of heavy metals in a suspended form, in bottom sediments and the spatial analysis for the results of these models were proposed and implemented. The studies were carried out during main hydrological seasons of 2014 - 2016 (during the flood and inter-natal periods). The propagation of heavy metals was modeled by solving the equation of turbulent diffusion. A spatial analysis of the content of heavy metals in the suspended form and in the bottom sediments was implemented by using the interpolation model in ArcGIS 10.2.2. The distribution of Pb, Hg, As concentration of the suspended form and bottom sediment phases in the estuary area of the Red River was characterized by maximum in the mouths of the branches and general decreasing gradient towards the sea. Maximum concentrations of Pb, Hg in suspended forms were observed in the surface layer of water at the river-sea barrier. The content of Hg and As in the estuary region of the Red River was observed in the following order: SSsurf< SSbott< BS; and content of Pb – SS >BS.

Biochemistry-directed hollow porous microspheres: bottom-up self-assembled polyanion-based cathodes for sodium ion batteries

NASA Astrophysics Data System (ADS)

Lin, Bo; Li, Qiufeng; Liu, Baodong; Zhang, Sen; Deng, Chao

2016-04-01

Biochemistry-directed synthesis of functional nanomaterials has attracted great interest in energy storage, catalysis and other applications. The unique ability of biological systems to guide molecule self-assembling facilitates the construction of distinctive architectures with desirable physicochemical characteristics. Herein, we report a biochemistry-directed ``bottom-up'' approach to construct hollow porous microspheres of polyanion materials for sodium ion batteries. Two kinds of polyanions, i.e. Na3V2(PO4)3 and Na3.12Fe2.44(P2O7)2, are employed as cases in this study. The microalgae cell realizes the formation of a spherical ``bottom'' bio-precursor. Its tiny core is subjected to destruction and its tough shell tends to carbonize upon calcination, resulting in the hollow porous microspheres for the ``top'' product. The nanoscale crystals of the polyanion materials are tightly enwrapped by the highly-conductive framework in the hollow microsphere, resulting in the hierarchical nano-microstructure. The whole formation process is disclosed as a ``bottom-up'' mechanism. Moreover, the biochemistry-directed self-assembly process is confirmed to play a crucial role in the construction of the final architecture. Taking advantage of the well-defined hollow-microsphere architecture, the abundant interior voids and the highly-conductive framework, polyanion materials show favourable sodium-intercalation kinetics. Both materials are capable of high-rate long-term cycling. After five hundred cycles at 20 C and 10 C, Na3V2(PO4)3 and Na3.12Fe2.44(P2O7)2 retain 96.2% and 93.1% of the initial capacity, respectively. Therefore, the biochemistry-directed technique provides a low-cost, highly-efficient and widely applicable strategy to produce high-performance polyanion-based cathodes for sodium ion batteries.Biochemistry-directed synthesis of functional nanomaterials has attracted great interest in energy storage, catalysis and other applications. The unique ability of biological systems to guide molecule self-assembling facilitates the construction of distinctive architectures with desirable physicochemical characteristics. Herein, we report a biochemistry-directed ``bottom-up'' approach to construct hollow porous microspheres of polyanion materials for sodium ion batteries. Two kinds of polyanions, i.e. Na3V2(PO4)3 and Na3.12Fe2.44(P2O7)2, are employed as cases in this study. The microalgae cell realizes the formation of a spherical ``bottom'' bio-precursor. Its tiny core is subjected to destruction and its tough shell tends to carbonize upon calcination, resulting in the hollow porous microspheres for the ``top'' product. The nanoscale crystals of the polyanion materials are tightly enwrapped by the highly-conductive framework in the hollow microsphere, resulting in the hierarchical nano-microstructure. The whole formation process is disclosed as a ``bottom-up'' mechanism. Moreover, the biochemistry-directed self-assembly process is confirmed to play a crucial role in the construction of the final architecture. Taking advantage of the well-defined hollow-microsphere architecture, the abundant interior voids and the highly-conductive framework, polyanion materials show favourable sodium-intercalation kinetics. Both materials are capable of high-rate long-term cycling. After five hundred cycles at 20 C and 10 C, Na3V2(PO4)3 and Na3.12Fe2.44(P2O7)2 retain 96.2% and 93.1% of the initial capacity, respectively. Therefore, the biochemistry-directed technique provides a low-cost, highly-efficient and widely applicable strategy to produce high-performance polyanion-based cathodes for sodium ion batteries. Electronic supplementary information (ESI) available: Synthesis, morphology and physical characteristics of reference samples; pore size distribution of the hollow porous microsphere; morphology of the bio-directed Na3.12Fe2.44(P2O7)2 hollow microsphere; comparison of the Rct values for the Na3.12Fe2.44(P2O7)2 composites; TEM images of the cycled materials; lattice parameters and atomic ratio of the samples; calculation process of sodium intercalation coefficients based on the GITT results. See DOI: 10.1039/c6nr00680a

Diffusion chamber system for testing of collagen-based cell migration barriers for separation of ligament enthesis zones in tissue-engineered ACL constructs.

PubMed

Hahner, J; Hoyer, M; Hillig, S; Schulze-Tanzil, G; Meyer, M; Schröpfer, M; Lohan, A; Garbe, L-A; Heinrich, G; Breier, A

2015-01-01

A temporary barrier separating scaffold zones seeded with different cell types prevents faster growing cells from overgrowing co-cultured cells within the same construct. This barrier should allow sufficient nutrient diffusion through the scaffold. The aim of this study was to test the effect of two variants of collagen-based barriers on macromolecule diffusion, viability, and the spreading efficiency of primary ligament cells on embroidered scaffolds. Two collagen barriers, a thread consisting of a twisted film tape and a sponge, were integrated into embroidered poly(lactic-co-caprolactone) and polypropylene scaffolds, which had the dimension of lapine anterior cruciate ligaments (ACL). A diffusion chamber system was designed and established to monitor nutrient diffusion using fluorescein isothiocyanate-labeled dextran of different molecular weights (20, 40, 150, 500 kDa). Vitality of primary lapine ACL cells was tested at days 7 and 14 after seeding using fluorescein diacetate and ethidium bromide staining. Cell spreading on the scaffold surface was measured using histomorphometry. Nuclei staining of the cross-sectioned scaffolds revealed the penetration of ligament cells through both barrier types. The diffusion chamber was suitable to characterize the diffusivity of dextran molecules through embroidered scaffolds with or without integrated collagen barriers. The diffusion coefficients were generally significantly lower in scaffolds with barriers compared to those without barriers. No significant differences between diffusion coefficients of both barrier types were detected. Both barriers were cyto-compatible and prevented most of the ACL cells from crossing the barrier, whereby the collagen thread was easier to handle and allowed a higher rate of cell spreading.

Patterning of organic photovoltaic on R2R processed thin film barriers using IR laser sources

NASA Astrophysics Data System (ADS)

Fledderus, H.; Akkerman, H. B.; Salem, A.; Friedrich Schilling, N.; Klotzbach, U.

2017-02-01

We present the development of laser processes for flexible OPV on roll-to-roll (RR2R) produced thin film barrier with indium tin oxide (ITO) as transparent conductive (TC) bottom electrode. Direct laser structuring of ITO on such barrier films (so-called P1 process) is very challenging since the layers are all transparent, a complete electrical isolation is required, and the laser process should not influence the barrier performance underneath the scribes. Based on the optical properties off the SiN and ITTO, ultra-short pulse lasers inn picosecond and femtosecond regime with standard infrared (IR) wavelength as well as lasers with new a wavelength (22 μm regime) are tested for this purpose. To determine a process window for a specific laser a fixed methodology is adopted. Single pulse ablation tests were followed by scribing experiments where the pulse overlap was tuned by varying laser pulse fluence, writing speed and frequency. To verify that the laser scribing does not result inn barrier damage underneath, a new test method was developed based on the optical Ca-test. This method shows a clear improvement in damage analysis underneath laser scribes over normal optical inspection methods (e.g. microscope, optical profiler, SEM). This way clear process windows can be obtained for IR TC patterning.

Bottom-up laboratory testing of the DKIST Visible Broadband Imager (VBI)

NASA Astrophysics Data System (ADS)

Ferayorni, Andrew; Beard, Andrew; Cole, Wes; Gregory, Scott; Wöeger, Friedrich

2016-08-01

The Daniel K. Inouye Solar Telescope (DKIST) is a 4-meter solar observatory under construction at Haleakala, Hawaii [1]. The Visible Broadband Imager (VBI) is a first light instrument that will record images at the highest possible spatial and temporal resolution of the DKIST at a number of scientifically important wavelengths [2]. The VBI is a pathfinder for DKIST instrumentation and a test bed for developing processes and procedures in the areas of unit, systems integration, and user acceptance testing. These test procedures have been developed and repeatedly executed during VBI construction in the lab as part of a "test early and test often" philosophy aimed at identifying and resolving issues early thus saving cost during integration test and commissioning on summit. The VBI team recently completed a bottom up end-to-end system test of the instrument in the lab that allowed the instrument's functionality, performance, and usability to be validated against documented system requirements. The bottom up testing approach includes four levels of testing, each introducing another layer in the control hierarchy that is tested before moving to the next level. First the instrument mechanisms are tested for positioning accuracy and repeatability using a laboratory position-sensing detector (PSD). Second the real-time motion controls are used to drive the mechanisms to verify speed and timing synchronization requirements are being met. Next the high-level software is introduced and the instrument is driven through a series of end-to-end tests that exercise the mechanisms, cameras, and simulated data processing. Finally, user acceptance testing is performed on operational and engineering use cases through the use of the instrument engineering graphical user interface (GUI). In this paper we present the VBI bottom up test plan, procedures, example test cases and tools used, as well as results from test execution in the laboratory. We will also discuss the benefits realized through completion of this testing, and share lessons learned from the bottoms up testing process.

The effect of transverse wave vector and magnetic fields on resonant tunneling times in double-barrier structures

NASA Astrophysics Data System (ADS)

Wang, Hongmei; Zhang, Yafei; Xu, Huaizhe

2007-01-01

The effect of transverse wave vector and magnetic fields on resonant tunneling times in double-barrier structures, which is significant but has been frequently omitted in previous theoretical methods, has been reported in this paper. The analytical expressions of the longitudinal energies of quasibound levels (LEQBL) and the lifetimes of quasibound levels (LQBL) in symmetrical double-barrier (SDB) structures have been derived as a function of transverse wave vector and longitudinal magnetic fields perpendicular to interfaces. Based on our derived analytical expressions, the LEQBL and LQBL dependence upon transverse wave vector and longitudinal magnetic fields has been explored numerically for a SDB structure. Model calculations show that the LEQBL decrease monotonically and the LQBL shorten with increasing transverse wave vector, and each original LEQBL splits to a series of sub-LEQBL which shift nearly linearly toward the well bottom and the lifetimes of quasibound level series (LQBLS) shorten with increasing Landau-level indices and magnetic fields.

Cohesiveness tunes assembly and morphology of FG nucleoporin domain meshworks – Implications for nuclear pore permeability

PubMed Central

Eisele, Nico B.; Labokha, Aksana A.; Frey, Steffen; Görlich, Dirk; Richter, Ralf P.

2013-01-01

Nuclear pore complexes control the exchange of macromolecules between the cytoplasm and the nucleus. A selective permeability barrier that arises from a supramolecular assembly of intrinsically unfolded nucleoporin domains rich in phenylalanine-glycine dipeptides (FG domains) fills the nuclear pore. There is increasing evidence that selective transport requires cohesive FG domain interactions. To understand the functional roles of cohesive interactions, we studied monolayers of end-grafted FG domains as a bottom-up nanoscale model system of the permeability barrier. Based on detailed physicochemical analysis of the model films and comparison of the data with polymer theory, we propose that cohesiveness is tuned to promote rapid assembly of the permeability barrier and to generate a stable and compact pore-filling meshwork with a small mesh size. Our results highlight the functional importance of weak interactions, typically a few kBT per chain, and contribute important information to understand the mechanism of size-selective transport. PMID:24138862

Text Processing Differences among Readers.

ERIC Educational Resources Information Center

Garner, Ruth

Explanations for differences in reading proficiency should be constructed around an atlas of reading-related individual differences in cognition. Such an atlas should include well-documented "bottom-up", text-driven reading strategies and less thoroughly investigated "top-down", schema-driven reading strategies. Research…

30 CFR 710.5 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... reclamation operations. Diversion means a channel, embankment, or other manmade structure constructed for the... direct response to precipitation in the immediate watershed and whose channel bottom is always above the... means precipitation that flows overland before entering a defined stream channel and becoming streamflow...

29 CFR 1615.151 - Program accessibility: New construction and alterations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... INFORMATION TECHNOLOGY § 1615.151 Program accessibility: New construction and alterations. Each building or... with disabilities. The definitions, requirements, and standards of the Architectural Barriers Act (42 U...

29 CFR 1615.151 - Program accessibility: New construction and alterations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... INFORMATION TECHNOLOGY § 1615.151 Program accessibility: New construction and alterations. Each building or... with disabilities. The definitions, requirements, and standards of the Architectural Barriers Act (42 U...

Alternative expression of vacuolar iron transporter and ferritin genes leads to blue/purple coloration of flowers in tulip cv. 'Murasakizuisho'.

PubMed

Shoji, Kazuaki; Momonoi, Kazumi; Tsuji, Tosiaki

2010-02-01

Flowers of tulip cv. 'Murasakizuisho' have a purple perianth except for the bottom region, which is blue in color even though it has the same anthocyanin, delphinidin 3-O-rutinoside, as the entire perianth. The development of the blue coloration in the perianth bottom is due to complexation by anthocyanin, flavonol and iron (Fe), as well as a vacuolar iron transporter, TgVit1. Although transient expression of TgVit1 in the purple cells led to a color change to light blue, the coloration of the transformed cells did not coincide with the dark blue color of the cells of the perianth bottom. We thought that another factor is required for the blue coloration of the cells of perianth bottom. To examine the effect of ferritin (FER), an Fe storage protein, on blue color development, we cloned an FER gene (TgFER1) and performed expression analyses. TgFER1 transcripts were found in the cells located in the upper region of the petals along with purple color development by anthocyanin and were not found in the blue cells of the perianth bottom. This gene expression is in contrast to that of TgVit1, expressed only in the cells of the perianth bottom. Co-expression of TgVIT1 and TgFER-RNAi, constructed for suppressing endogenous TgFER1 by RNA interference (RNAi), changed the purple petal cells to a dark blue color similar to that of the natural perianth bottom. These results strongly suggest that TgVit1 expression and TgFER1 suppression are critical for the development of blue color in the perianth bottom.

Developmental Dynamics of General and School-Subject-Specific Components of Academic Self-Concept, Academic Interest, and Academic Anxiety

PubMed Central

Gogol, Katarzyna; Brunner, Martin; Preckel, Franzis; Goetz, Thomas; Martin, Romain

2016-01-01

The present study investigated the developmental dynamics of general and subject-specific (i.e., mathematics, French, and German) components of students' academic self-concept, anxiety, and interest. To this end, the authors integrated three lines of research: (a) hierarchical and multidimensional approaches to the conceptualization of each construct, (b) longitudinal analyses of bottom-up and top-down developmental processes across hierarchical levels, and (c) developmental processes across subjects. The data stemmed from two longitudinal large-scale samples (N = 3498 and N = 3863) of students attending Grades 7 and 9 in Luxembourgish schools. Nested-factor models were applied to represent each construct at each grade level. The analyses demonstrated that several characteristics were shared across constructs. All constructs were multidimensional in nature with respect to the different subjects, showed a hierarchical organization with a general component at the apex of the hierarchy, and had a strong separation between the subject-specific components at both grade levels. Further, all constructs showed moderate differential stabilities at both the general (0.42 < r < 0.55) and subject-specific levels (0.45 < r < 0.73). Further, little evidence was found for top-down or bottom-up developmental processes. Rather, general and subject-specific components in Grade 9 proved to be primarily a function of the corresponding components in Grade 7. Finally, change in several subject-specific components could be explained by negative effects across subjects. PMID:27014162

Developmental Dynamics of General and School-Subject-Specific Components of Academic Self-Concept, Academic Interest, and Academic Anxiety.

PubMed

Gogol, Katarzyna; Brunner, Martin; Preckel, Franzis; Goetz, Thomas; Martin, Romain

2016-01-01

The present study investigated the developmental dynamics of general and subject-specific (i.e., mathematics, French, and German) components of students' academic self-concept, anxiety, and interest. To this end, the authors integrated three lines of research: (a) hierarchical and multidimensional approaches to the conceptualization of each construct, (b) longitudinal analyses of bottom-up and top-down developmental processes across hierarchical levels, and (c) developmental processes across subjects. The data stemmed from two longitudinal large-scale samples (N = 3498 and N = 3863) of students attending Grades 7 and 9 in Luxembourgish schools. Nested-factor models were applied to represent each construct at each grade level. The analyses demonstrated that several characteristics were shared across constructs. All constructs were multidimensional in nature with respect to the different subjects, showed a hierarchical organization with a general component at the apex of the hierarchy, and had a strong separation between the subject-specific components at both grade levels. Further, all constructs showed moderate differential stabilities at both the general (0.42 < r < 0.55) and subject-specific levels (0.45 < r < 0.73). Further, little evidence was found for top-down or bottom-up developmental processes. Rather, general and subject-specific components in Grade 9 proved to be primarily a function of the corresponding components in Grade 7. Finally, change in several subject-specific components could be explained by negative effects across subjects.

Delineation systems for temporary traffic barriers in work zones.

DOT National Transportation Integrated Search

1986-01-01

Providing for the safety of traffic traversing construction and maintenance work zones is becoming increasingly complex, and over the past several years, temporary concrete barriers have come into use as a means of protecting work crews as well as mo...

Use of Barriers in Rural Open Road Conditions--A Synthesis Study

DOT National Transportation Integrated Search

2012-05-01

The use of wide medians and clear zones that do not require median and roadside barriers is the current design practice for new and : reconstructed rural highway facilities. Constructing or reconstructing roads with fullwidth medians and clear zon...

Use of Barriers in Rural Open Road Condition--A Synthesis Study

DOT National Transportation Integrated Search

2012-05-01

The use of wide medians and clear zones that do not require median and roadside barriers is the current design practice for new and : reconstructed rural highway facilities. Constructing or reconstructing roads with fullwidth medians and clear zon...

44 CFR 206.344 - Limitations on Federal expenditures.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., DEPARTMENT OF HOMELAND SECURITY DISASTER ASSISTANCE FEDERAL DISASTER ASSISTANCE Coastal Barrier Resources Act... within the Coastal Barrier Resources System, including but not limited to: (a) Construction... area, except that such assistance and expenditures may be made available on units designated pursuant...

40 CFR 267.1103 - What additional design and operating standards apply if liquids will be in my containment building?

Code of Federal Regulations, 2011 CFR

2011-07-01

... the migration of hazardous constituents into the barrier (for example, a geomembrane covered by a... containment system, including a secondary barrier designed and constructed to prevent migration of hazardous...

40 CFR 267.1103 - What additional design and operating standards apply if liquids will be in my containment building?

Code of Federal Regulations, 2010 CFR

2010-07-01

... the migration of hazardous constituents into the barrier (for example, a geomembrane covered by a... containment system, including a secondary barrier designed and constructed to prevent migration of hazardous...

Mitigation of lava flow invasion hazard through optimized barrier configuration aided by numerical simulation: The case of the 2001 Etna eruption

NASA Astrophysics Data System (ADS)

Scifoni, S.; Coltelli, M.; Marsella, M.; Proietti, C.; Napoleoni, Q.; Vicari, A.; Del Negro, C.

2010-04-01

Lava flow spreading along the flanks of Etna volcano often produces damages to the land and proprieties. The impact of these eruptions could be mitigated by building artificial barriers for controlling and slowing down the lava, as recently experienced in 1983, 1991-1993, 2001 and 2002. This study investigates how numerical simulations can be adopted for evaluating the effectiveness of barrier construction and for optimizing their geometry, considering as test case the lava flows emplaced on Etna's south flank during 2001. The flow temporal evolutions were reconstructed deriving the effusion rate trends, together with the pre-eruption topography were adopted as input data of the MAGFLOW simulation code. Three simulations were then conducted to simulate lava flow with and without barriers. The first aimed at verifying the reconstruction of the effusion rate trends, while the others at assessing the performance of the barrier system realized during the eruption in comparison with an alternative solution here proposed. A quantitative analysis carried out on the first simulation confirms the suitability of the selected test case. The comparison of the three simulated thickness distributions showed both the effectiveness of the barriers in slowing down the lava flow and the sensitivity of the MAGFLOW code to the topographical variations represented by the barriers. Finally, for reducing both the time necessary to erect the barrier and the barrier environmental impact, the gabion's barrier construction was analyzed. The implemented and tested procedure enforces the capability of using numerical simulations for designing optimized lava flow barriers aimed at making swifter mitigatory actions upon lava flows and improving the effectiveness of civil protection interventions during emergencies.

Tuning spin-polarized transport in organic semiconductors

NASA Astrophysics Data System (ADS)

Mattana, Richard; Galbiati, Marta; Delprat, Sophie; Tatay, Sergio; Deranlot, Cyrile; Seneor, Pierre; Petroff, Frederic

Molecular spintronics is an emerging research field at the frontier between organic chemistry and the spintronics. Compared to traditional inorganic materials molecules are flexible and can be easily tailored by chemical synthesis. Due to their theoretically expected very long spin lifetime, they were first only seen as the ultimate media for spintronics devices. It was recently that new spintronics tailoring could arise from the chemical versatility brought by molecules. The hybridization between a ferromagnet and molecules induces a spin dependent broadening and energy shifting of the molecular orbitals leading to an induced spin polarization on the first molecular layer. This spin dependent hybridization can be used to tailor the spin dependent transport in organic spintronics devices. We have studied vertical Co/Alq3/Co organic spin valves. The negative magnetoresistance observed is the signature of different coupling strengths at the top and bottom interfaces. We have then inserted an inorganic tunnel barrier at the bottom interface in order to suppress the spin-dependent hybridization. In this case we restore a positive magnetoresistance. This demonstrates that at the bottom Co/Alq3 interface a stronger coupling occurs which induces an inversion of the spin polarization.

Capillary Liquid Acquisition Device Heat Entrapment

NASA Technical Reports Server (NTRS)

Bolshinskiy, L. G.; Hastings, L. J.; Statham, G.; Turpin, J. B.

2007-01-01

Cryogenic liquid acquisition devices (LADs) for space-based propulsion interface directly with the feed system, which can be a significant heat leak source. Further, the accumulation of thermal energy within LAD channels can lead to the loss of subcooled propellant conditions and result in feed system cavitation during propellant outflow. Therefore, the fundamental question addressed by this program was: To what degree is natural convection in a cryogenic liquid constrained by the capillary screen meshes envisioned for LADs? Testing was first conducted with water as the test fluid, followed by LN2 tests. In either case, the basic experimental approach was to heat the bottom of a cylindrical column of test fluid to establish stratification patterns measured by temperature sensors located above and below a horizontal screen barrier position. Experimentation was performed without barriers, with screens, and with a solid barrier. The two screen meshes tested were those typically used by LAD designers, 200x1400 and 325x2300, both with Twill Dutch Weave. Upon consideration of both the water and LN2 data, it was concluded that heat transfer across the screen meshes was dependent upon barrier thermal conductivity and that the capillary screen meshes were impervious to natural convection currents.

Cryogenic Capillary Screen Heat Entrapment

NASA Technical Reports Server (NTRS)

Bolshinskiy, L.G.; Hastings, L.J.; Stathman, G.

2007-01-01

Cryogenic liquid acquisition devices (LADs) for space-based propulsion interface directly with the feed system, which can be a significant heat leak source. Further, the accumulation of thermal energy within LAD channels can lead to the loss of sub-cooled propellant conditions and result in feed system cavitation during propellant outflow. Therefore, the fundamental question addressed by this program was: "To what degree is natural convection in a cryogenic liquid constrained by the capillary screen meshes envisioned for LADs.?"Testing was first conducted with water as the test fluid, followed by LN2 tests. In either case, the basic experimental approach was to heat the bottom of a cylindrical column of test fluid to establish stratification patterns measured by temperature sensors located above and below a horizontal screen barrier position. Experimentation was performed without barriers, with screens, and with a solid barrier. The two screen meshes tested were those typically used by LAD designers, "200x1400" and "325x2300", both with Twill Dutch Weave. Upon consideration of both the water and LN2 data it was concluded that heat transfer across the screen meshes was dependent upon barrier thermal conductivity and that the capillary screen meshes were impervious to natural convection currents.

A simple cell transport device keeps culture alive and functional during shipping.

PubMed

Miller, Paula G; Wang, Ying I; Swan, Glen; Shuler, Michael L

2017-09-01

Transporting living complex cellular constructs through the mail while retaining their full viability and functionality is challenging. During this process, cells often suffer from exposure to suboptimal life-sustaining conditions (e.g. temperature, pH), as well as damage due to shear stress. We have developed a transport device for shipping intact cell/tissue constructs from one facility to another that overcomes these obstacles. Our transport device maintained three different cell lines (Caco2, A549, and HepG2 C3A) individually on transwell membranes with high viability (above 97%) for 48 h under simulated shipping conditions without an incubator. The device was also tested by actual overnight shipping of blood brain barrier constructs consisting of human induced pluripotent brain microvascular endothelial cells and rat astrocytes on transwell membranes to a remote facility (approximately 1200 miles away). The blood brain barrier constructs arrived with high cell viability and were able to regain full barrier integrity after equilibrating in the incubator for 24 h; this was assessed by the presence of continuous tight junction networks and in vivo-like values for trans-endothelial electrical resistance (TEER). These results demonstrated that our cell transport device could be a useful tool for long-distance transport of membrane-bound cell cultures and functional tissue constructs. Studies that involve various cell and tissue constructs, such as the "Multi-Organ-on-Chip" devices (where multiple microscale tissue constructs are integrated on a single microfluidic device) and studies that involve microenvironments where multiple tissue interactions are of interest, would benefit from the ability to transport or receive these constructs. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1257-1266, 2017. © 2017 American Institute of Chemical Engineers.

A Survey of Homework Use, Experience of Barriers to Homework, and Attitudes about the Barriers to Homework among Couples and Family Therapists

ERIC Educational Resources Information Center

Dattilio, Frank M.; Kazantzis, Nikolaos; Shinkfield, Gregg; Carr, Amanda G.

2011-01-01

Homework is a therapeutic process that has strong theoretical and empirical basis, but existing research has focused on "compliance" rather than considering the broader and more clinically meaningful construct of "engagement." Absent in the literature is empirical study of the barriers to engagement or study of homework use among couple and family…

Thermal treatment of stabilized air pollution control residues in a waste incinerator pilot plant. Part 2: Leaching characteristics of bottom ashes.

PubMed

Baun, Dorthe L; Christensen, Thomas H; Bergfeldt, Brita; Vehlow, Jürgen; Mogensen, Erhardt P B

2004-02-01

With the perspective of generating only one solid residue from waste incineration, co-feeding of municipal solid waste and air pollution control residues stabilized by the Ferrox process was investigated in the TAMARA pilot plant incinerator as described in Bergfeldt et al. (Waste Management Research, 22, 49-57, 2004). This paper reports on leaching from the combined bottom ashes. Batch leaching test, pH-static leaching tests, availability tests and column leaching tests were used to characterize the leaching properties. The leaching properties are key information in the context of reuse in construction or in landfilling of the combined residue. In general, the combined bottom ashes had leaching characteristics similar to the reference bottom ash, which contained no APC residue. However, As and Pb showed slightly elevated leaching from the combined bottom ashes, while Cr showed less leaching. The investigated combined bottom ashes had contents of metals comparable to what is expected at steady state after continuous co-feeding of APC residues. Only Cd and Pb were partly volatilized (30-40%) during the incineration process and thus the combined bottom ashes had lower contents of Cd and Pb than expected at steady state. Furthermore, a major loss of Hg was, not surprisingly, seen and co-feeding of Ferrox-products together with municipal solid waste will require dedicated removal of Hg in the flue gas to prevent a build up of Hg in the system. In spite of this, a combined single solid residue from waste incineration seems to be a significant environmental improvement to current technology.

Oligocene to Holocene sediment drifts and bottom currents on the slope of Gabon continental margin (west Africa). Consequences for sedimentation and southeast Atlantic upwelling

NASA Astrophysics Data System (ADS)

Séranne, Michel; Nzé Abeigne, César-Rostand

1999-10-01

Seismic reflection profiles on the slope of the south Gabon continental margin display furrows 2 km wide and some 200 m deep, that develop normal to the margin in 500-1500 m water depth. Furrows are characterised by an aggradation/progradation pattern which leads to margin-parallel, northwestward migration of their axes through time. These structures, previously interpreted as turbidity current channels, display the distinctive seismic image and internal organisation of sediment drifts, constructed by the activity of bottom currents. Sediment drifts were initiated above a major Oligocene unconformity, and they developed within a Oligocene to Present megasequence of general progradation of the margin, whilst they are markedly absent from the underlying Late Cretaceous-Eocene aggradation megasequence. The presence of upslope migrating sediment waves, and the northwest migration of the sediment drifts indicate deposition by bottom current flowing upslope, under the influence of the Coriolis force. Such landwards-directed bottom currents on the slope probably represent coastal upwelling, which has been active along the west Africa margin throughout the Neogene.

Glass-ceramic from mixtures of bottom ash and fly ash.

PubMed

Vu, Dinh Hieu; Wang, Kuen-Sheng; Chen, Jung-Hsing; Nam, Bui Xuan; Bac, Bui Hoang

2012-12-01

Along with the gradually increasing yield of the residues, appropriate management and treatment of the residues have become an urgent environmental protection problem. This work investigated the preparation of a glass-ceramic from a mixture of bottom ash and fly ash by petrurgic method. The nucleation and crystallization kinetics of the new glass-ceramic can be obtained by melting the mixture of 80% bottom ash and 20% fly ash at 950 °C, which was then cooled in the furnace for 1h. Major minerals forming in the glass-ceramics mainly are gehlenite (Ca(2)Al(2)SiO(7)) & akermanite (Ca(2)MgSiO(7)) and wollastonite (CaSiO(3)). In addition, regarding chemical/mechanical properties, the chemical resistance showing durability, and the leaching concentration of heavy metals confirmed the possibility of engineering and construction applications of the most superior glass-ceramic product. Finally, petrurgic method of a mixture of bottom ash and fly ash at 950 °C represents a simple, inexpensive, and energy saving method compared with the conventional heat treatment. Copyright © 2012 Elsevier Ltd. All rights reserved.

Evaluating the use of waste-to-energy bottom ash as road construction materials : [summary].

DOT National Transportation Integrated Search

2014-02-01

Municipal solid waste incineration (MSWI) generates millions of tons of ash each year. In European and Asian countries, this ash has been recycled into road beds, asphalt paving, and concrete products encouraged and enforced by standards, managem...

Role of coordination geometry in dictating the barrier to hydride migration in d6 square-pyramidal iridium and rhodium pincer complexes.

PubMed

Findlater, Michael; Cartwright-Sykes, Alison; White, Peter S; Schauer, Cynthia K; Brookhart, Maurice

2011-08-10

Syntheses of the olefin hydride complexes [(POCOP)M(H)(olefin)][BAr(f)(4)] (6a-M, M = Ir or Rh, olefin = C(2)H(4); 6b-M, M = Ir or Rh, olefin = C(3)H(6); POCOP = 2,6-bis(di-tert-butylphosphinito)benzene; BAr(f) = tetrakis(3,5-trifluoromethylphenyl)borate) are reported. A single-crystal X-ray structure determination of 6b-Ir shows a square-pyramidal coordination geometry for Ir, with the hydride ligand occupying the apical position. Dynamic NMR techniques were used to characterize these complexes. The rates of site exchange between the hydride and the olefinic hydrogens yielded ΔG(++) = 15.6 (6a-Ir), 16.8 (6b-Ir), 12.0 (6a-Rh), and 13.7 (6b-Rh) kcal/mol. The NMR exchange data also established that hydride migration in the propylene complexes yields exclusively the primary alkyl intermediate arising from 1,2-insertion. Unexpectedly, no averaging of the top and bottom faces of the square-pyramidal complexes is observed in the NMR spectra at high temperatures, indicating that the barrier for facial equilibration is >20 kcal/mol for both the Ir and Rh complexes. A DFT computational study was used to characterize the free energy surface for the hydride migration reactions. The classical terminal hydride complexes, [M(POCOP)(olefin)H](+), are calculated to be the global minima for both Rh and Ir, in accord with experimental results. In both the Rh ethylene and propylene complexes, the transition state for hydride migration (TS1) to form the agostic species is higher on the energy surface than the transition state for in-place rotation of the coordinated C-H bond (TS2), while for Ir, TS2 is the high point on the energy surface. Therefore, only for the case of the Rh complexes is the NMR exchange rate a direct measure of the hydride migration barrier. The trends in the experimental barriers as a function of M and olefin are in good agreement with the trends in the calculated exchange barriers. The calculated barriers for the hydride migration reaction in the Rh complexes are ∼2 kcal/mol higher than for the Ir complexes, despite the fact that the energy difference between the olefin hydride ground state and the agostic alkyl structure is ∼4 kcal/mol larger for Ir than for Rh. This feature, together with the high barrier for interchange of the top and bottom faces of the complexes, is proposed to arise from the unique coordination geometry of the agostic complexes and the strong preference for a cis-divacant octahedral geometry in four-coordinate intermediates. © 2011 American Chemical Society

Prediction of barrier island restoration response and its interactions with the natural environment

NASA Astrophysics Data System (ADS)

Plant, N. G.; Stockdon, H. F.; Flocks, J.; Sallenger, A. H.; Long, J. W.; Cormier, J. M.; Guy, K.; Thompson, D. M.

2012-12-01

A 2-meter high sand berm was constructed along Chandeleur Island, Louisiana, in an attempt to provide protection against the Deepwater Horizon oil spill. Berm construction started in June 2010 and ended in April 2011. Variations in both island morphology and construction of the 15-km long berm resulted in the development of four different morphologies: a berm built on a submerged island platform to the north of the existing island, a berm built seaward of the existing island, a berm built along the island shoreline, and portions of the island where no berm was constructed. These different morphologies provide a natural laboratory for testing the understanding of berm and barrier island response to storms. In particular, the ability to predict berm evolution using statistical modeling of the interactions between the island, berm, and oceanographic processes was tested. This particular test was part of a broader USGS research effort to understand processes that bridge the gap between short-term storm response and longer-term geologic and climate interactions that shape barrier-island systems. Berm construction and subsequent berm and island evolution were monitored using satellite and aerial remote sensing and topographic and bathymetric surveys. To date, significant berm evolution occurred in both the north (including terminal erosion, overwash, and a large breach), center (overwash and numerous breaches), and south (overwash). The response of the central portion of the berm to winter and tropical storms was significant such that none of the residual berm remained within its construction footprint. The evolution of the central portion of the berm was well predicted using a statistical modeling approach that used predicted and modeled wave conditions to identify the likelihood of overwash events. Comparison of different modeled evolution scenarios to the one that was observed showed that berm response was sensitive to the frequency and severity of winter and tropical storms. These findings demonstrate an observation and modeling approach that can be applied to understanding and managing other natural and restored barrier islands.

75 FR 17829 - Motorcyclist Advisory Council to the Federal Highway Administration

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-07

... FHWA, on infrastructure issues of concern to motorcyclists, including: (1) Barrier design; (2) road design, construction, and maintenance practices; and (3) the architecture and implementation of... Administrator on infrastructure issues of concern to motorcyclists, including-- (1) Barrier design; (2) Road...

46 CFR 154.459 - General.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Secondary Barrier § 154.459 General. (a) Each cargo tank must have a secondary barrier that meets Table 3 and except as...

44 CFR 206.344 - Limitations on Federal expenditures.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., DEPARTMENT OF HOMELAND SECURITY DISASTER ASSISTANCE FEDERAL DISASTER ASSISTANCE Coastal Barrier Resources Act... within the Coastal Barrier Resources System, including but not limited to: (a) Construction... any project to prevent the erosion of, or to otherwise stabilize, any inlet, shoreline, or inshore...

44 CFR 206.344 - Limitations on Federal expenditures.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., DEPARTMENT OF HOMELAND SECURITY DISASTER ASSISTANCE FEDERAL DISASTER ASSISTANCE Coastal Barrier Resources Act... within the Coastal Barrier Resources System, including but not limited to: (a) Construction... any project to prevent the erosion of, or to otherwise stabilize, any inlet, shoreline, or inshore...

44 CFR 206.344 - Limitations on Federal expenditures.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., DEPARTMENT OF HOMELAND SECURITY DISASTER ASSISTANCE FEDERAL DISASTER ASSISTANCE Coastal Barrier Resources Act... within the Coastal Barrier Resources System, including but not limited to: (a) Construction... any project to prevent the erosion of, or to otherwise stabilize, any inlet, shoreline, or inshore...

44 CFR 206.344 - Limitations on Federal expenditures.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., DEPARTMENT OF HOMELAND SECURITY DISASTER ASSISTANCE FEDERAL DISASTER ASSISTANCE Coastal Barrier Resources Act... within the Coastal Barrier Resources System, including but not limited to: (a) Construction... any project to prevent the erosion of, or to otherwise stabilize, any inlet, shoreline, or inshore...

Development of MASH TL-3 transition between guardrail and portable concrete barriers.

DOT National Transportation Integrated Search

2014-06-01

Often, road construction causes the need to create a work zone. In these scenarios, portable concrete barriers (PCBs) : are typically installed to shield workers and equipment from errant vehicles as well as prevent motorists from striking other : ro...

Impact of bimetal electrodes on dielectric properties of TiO2 and Al-doped TiO2 films.

PubMed

Kim, Seong Keun; Han, Sora; Jeon, Woojin; Yoon, Jung Ho; Han, Jeong Hwan; Lee, Woongkyu; Hwang, Cheol Seong

2012-09-26

Rutile structured Al-doped TiO(2) (ATO) and TiO(2) films were grown on bimetal electrodes (thin Ru/thick TiN, Pt, and Ir) for high-performance capacitors. The work function of the top Ru layer decreased on TiN and increased on Pt and Ir when it was thinner than ~2 nm, suggesting that the lower metal within the electrodes influences the work function of the very thin Ru layer. The use of the lower electrode with a high work function for bottom electrode eventually improves the leakage current properties of the capacitor at a very thin Ru top layer (≤2 nm) because of the increased Schottky barrier height at the interface between the dielectric and the bottom electrode. The thin Ru layer was necessary to achieve the rutile structured ATO and TiO(2) dielectric films.

Only Above Barrier Energy Components Contribute to Barrier Traversal Time

NASA Astrophysics Data System (ADS)

Galapon, Eric A.

2012-04-01

A time of arrival operator across a square potential barrier is constructed. The expectation value of the barrier time of arrival operator for a sufficiently localized incident wave packet is compared with the expectation value of the free particle time of arrival operator for the same wave packet. The comparison yields an expression for the expected traversal time across the barrier. It is shown that only the above barrier components of the momentum distribution of the incident wave packet contribute to the barrier traversal time, implying that below the barrier components are transmitted without delay. This is consistent with the recent experiment in attosecond ionization in helium indicating that there is no real tunneling delay time [P. Eckle , Science 322, 1525 (2008)SCIEAS0036-807510.1126/science.1163439].

Comparing barrier algorithms

NASA Technical Reports Server (NTRS)

Arenstorf, Norbert S.; Jordan, Harry F.

1987-01-01

A barrier is a method for synchronizing a large number of concurrent computer processes. After considering some basic synchronization mechanisms, a collection of barrier algorithms with either linear or logarithmic depth are presented. A graphical model is described that profiles the execution of the barriers and other parallel programming constructs. This model shows how the interaction between the barrier algorithms and the work that they synchronize can impact their performance. One result is that logarithmic tree structured barriers show good performance when synchronizing fixed length work, while linear self-scheduled barriers show better performance when synchronizing fixed length work with an imbedded critical section. The linear barriers are better able to exploit the process skew associated with critical sections. Timing experiments, performed on an eighteen processor Flex/32 shared memory multiprocessor, that support these conclusions are detailed.

Re-using biological devices: a model-aided analysis of interconnected transcriptional cascades designed from the bottom-up.

PubMed

Pasotti, Lorenzo; Bellato, Massimo; Casanova, Michela; Zucca, Susanna; Cusella De Angelis, Maria Gabriella; Magni, Paolo

2017-01-01

The study of simplified, ad-hoc constructed model systems can help to elucidate if quantitatively characterized biological parts can be effectively re-used in composite circuits to yield predictable functions. Synthetic systems designed from the bottom-up can enable the building of complex interconnected devices via rational approach, supported by mathematical modelling. However, such process is affected by different, usually non-modelled, unpredictability sources, like cell burden. Here, we analyzed a set of synthetic transcriptional cascades in Escherichia coli . We aimed to test the predictive power of a simple Hill function activation/repression model (no-burden model, NBM) and of a recently proposed model, including Hill functions and the modulation of proteins expression by cell load (burden model, BM). To test the bottom-up approach, the circuit collection was divided into training and test sets, used to learn individual component functions and test the predicted output of interconnected circuits, respectively. Among the constructed configurations, two test set circuits showed unexpected logic behaviour. Both NBM and BM were able to predict the quantitative output of interconnected devices with expected behaviour, but only the BM was also able to predict the output of one circuit with unexpected behaviour. Moreover, considering training and test set data together, the BM captures circuits output with higher accuracy than the NBM, which is unable to capture the experimental output exhibited by some of the circuits even qualitatively. Finally, resource usage parameters, estimated via BM, guided the successful construction of new corrected variants of the two circuits showing unexpected behaviour. Superior descriptive and predictive capabilities were achieved considering resource limitation modelling, but further efforts are needed to improve the accuracy of models for biological engineering.

Review of Graphene as a Solid State Diffusion Barrier.

PubMed

Morrow, Wayne K; Pearton, Stephen J; Ren, Fan

2016-01-06

Conventional thin-film diffusion barriers consist of 3D bulk films with high chemical and thermal stability. The purpose of the barrier material is to prevent intermixing or penetration from the two materials that encase it. Adhesion to both top and bottom materials is critical to the success of the barrier. Here, the effectiveness of a single atomic layer of graphene as a solid-state diffusion barrier for common metal schemes used in microelectronics is reviewed, and specific examples are discussed. Initial studies of electrical contacts to graphene show a distinct separation in behavior between metallic groups that strongly or weakly bond to it. The two basic classes of metal reactions with graphene are either physisorbed metals, which bond weakly with graphene, or chemisorbed metals, which bond strongly to graphene. For graphene diffusion barrier testing on Si substrates, an effective barrier can be achieved through the formation of a carbide layer with metals that are chemisorbed. For physisorbed metals, the barrier failure mechanism is loss of adhesion at the metal–graphene interface. A graphene layer encased between two metal layers, in certain cases, can increase the binding energy of both films with graphene, however, certain combinations of metal films are detrimental to the bonding with graphene. While the prospects for graphene's future as a solid-state diffusion barrier are positive, there are open questions, and areas for future research are discussed. A better understanding of the mechanisms which influence graphene's ability to be an effective diffusion barrier in microelectronic applications is required, and additional experiments are needed on a broader range of metals, as well as common metal stack contact structures used in microelectronic applications. The role of defects in the graphene is also a key area, since they will probably influence the barrier properties. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Measured airtightness of 24 detached houses over periods of up to three years

DOE Office of Scientific and Technical Information (OSTI.GOV)

Proskiw, G.

1995-09-01

Regular airtightness tests were performed on 24 new houses, over periods of up to three years, to evaluate their air barrier systems and to search for evidence, air barrier degradation. Ten of the houses were constructed with polyethylene air barriers while the remaining 14 used an early version of the Airtight Drywall Approach (ADA). The 24 project houses were architecturally similar and of approximately equal size and general layout; stucco was the predominate exterior wall finish. All were exposed to similar terrain shielding. The study found that the airtightness of the polyethylene air barrier houses remained stable over their respectivemore » monitoring periods. Although two of the ten houses demonstrated possible, albeit slight, evidence of airtightness degradation, the magnitude of these changes was small and judged not to be of practical significance. With respect to the critical issue of air barrier degradation, no evidence could be found to indicate polyethylene is unsuited for use as an air barrier material in residential construction. For example, all but one of the polyethylene houses met the airtightness requirements of the Canadian R-2000 Standard for energy efficient housing at the end of their monitoring periods. The study found that the airtightness of the 14 ADA houses also remained stable over their monitoring periods. Although six of the 14 houses displayed possible, but slight, evidence of airtightness degradation, the magnitude of the changes was small and not of practical significance. It was concluded that no evidence could be found to indicate that the ADA system is unsuited for use in residential construction. All 14 ADA houses met the airtightness requirements of the R-2000 Program at the end of their respective monitoring periods.« less

[Construction and validation of a short scale of perception of barriers for the physical activity in adolescents].

PubMed

Cabanas-Sánchez, Verónica; Tejero-González, Carlos M; Veiga, Oscar L

2012-01-01

One of the main problems of health in the first world is the increase of physical inactivity. In this respect, adolescence has been identified as a critic period with high decline of physical activity. Therefore, a relevant line of research is the understanding of this social phenomenon. The aim of this study was to design a scale to assess perceived barriers to physical activity on adolescents. A convenience sample of 160 Spanish adolescents (84 girls), between 12 and 18 years old, was recruited for this study. Firstly, there were designed 40 items whose pertinence was evaluated through content validation by experts. Later, the participants were divided in two randomized groups, and Exploratory Factor Analysis and Confirmatory Factor Analysis were performed to define a short scale of 12 items. Cronbach Alfa Coefficent was used to evaluate internal consistence of the instrument. The scale reports four dimensions: incompatibility barriers (2 items), self-concept barriers (4 items), amotivation barriers (4 items) and social barriers (2 items). The scale showed enough construct validity (χ2=60.78; d.f.=48; p=0.100; GFI=0.88; CFI=0.94; RMSEA=0.58) and high internal reliability (α=0.80). Moreover, the scale was able to explain 67% of the data variance. The Short Scale of Perceived Barriers to Physical Activity in Adolescents is a valid and reliable instrument.

Disentangling the Importance of Psychological Predispositions and Social Constructions in the Organization of American Political Ideology.

PubMed

Verhulst, Brad; Hatemi, Peter K; Eaves, Lindon J

2012-06-01

Ideological preferences within the American electorate are contingent on both the environmental conditions that provide the content of the contemporary political debate and internal predispositions that motivate people to hold liberal or conservative policy preferences. In this article we apply Jost, Federico, and Napier's (2009) top-down/bottom-up theory of political attitude formation to a genetically informative population sample. In doing so, we further develop the theory by operationalizing the top-down pathway to be a function of the social environment and the bottom-up pathway as a latent set of genetic factors. By merging insights from psychology, behavioral genetics, and political science, we find strong support for the top-down/bottom-up framework that segregates the two independent pathways in the formation of political attitudes and identifies a different pattern of relationships between political attitudes at each level of analysis.

Homoepitaxial graphene tunnel barriers for spin transport (Presentation Recording)

NASA Astrophysics Data System (ADS)

Friedman, Adam L.

2015-09-01

Tunnel barriers are key elements for both charge-and spin-based electronics, offering devices with reduced power consumption and new paradigms for information processing. Such devices require mating dissimilar materials, raising issues of heteroepitaxy, interface stability, and electronic states that severely complicate fabrication and compromise performance. Graphene is the perfect tunnel barrier. It is an insulator out-of-plane, possesses a defect-free, linear habit, and is impervious to interdiffusion. Nonetheless, true tunneling between two stacked graphene layers is not possible in environmental conditions (magnetic field, temperature, etc.) usable for electronics applications. However, two stacked graphene layers can be decoupled using chemical functionalization. Here, we demonstrate homoepitaxial tunnel barrier devices in which graphene serves as both the tunnel barrier and the high mobility transport channel. Beginning with multilayer graphene, we fluorinate or hydrogenate the top layer to decouple it from the bottom layer, so that it serves as a single monolayer tunnel barrier for both charge and spin injection into the lower graphene transport channel. We demonstrate successful tunneling by measuring non-linear IV curves, and a weakly temperature dependent zero bias resistance. We perform lateral transport of spin currents in non-local spin-valve structures and determine spin lifetimes with the non-local Hanle effect to be commensurate with previous studies (~200 ps). However, we also demonstrate the highest spin polarization efficiencies (~45%) yet measured in graphene-based spin devices [1]. [1] A.L. Friedman, et al., Homoepitaxial tunnel barriers with functionalized graphene-on-graphene for charge and spin transport, Nat. Comm. 5, 3161 (2014).

CMOS compatible electrode materials selection in oxide-based memory devices

NASA Astrophysics Data System (ADS)

Zhuo, V. Y.-Q.; Li, M.; Guo, Y.; Wang, W.; Yang, Y.; Jiang, Y.; Robertson, J.

2016-07-01

Electrode materials selection guidelines for oxide-based memory devices are constructed from the combined knowledge of observed device operation characteristics, ab-initio calculations, and nano-material characterization. It is demonstrated that changing the top electrode material from Ge to Cr to Ta in the Ta2O5-based memory devices resulted in a reduction of the operation voltages and current. Energy Dispersed X-ray (EDX) Spectrometer analysis clearly shows that the different top electrode materials scavenge oxygen ions from the Ta2O5 memory layer at various degrees, leading to different oxygen vacancy concentrations within the Ta2O5, thus the observed trends in the device performance. Replacing the Pt bottom electrode material with CMOS compatible materials (Ru and Ir) further reduces the power consumption and can be attributed to the modification of the Schottky barrier height and oxygen vacancy concentration at the electrode/oxide interface. Both trends in the device performance and EDX results are corroborated by the ab-initio calculations which reveal that the electrode material tunes the oxygen vacancy concentration via the oxygen chemical potential and defect formation energy. This experimental-theoretical approach strongly suggests that the proper selection of CMOS compatible electrode materials will create the critical oxygen vacancy concentration to attain low power memory performance.

Quantification of pore clogging characteristics in potential permeable reactive barrier (PRB) substrates using image analysis.

PubMed

Wantanaphong, J; Mooney, S J; Bailey, E H

2006-08-10

Permeable reactive barriers (PRBs) are now an established approach for groundwater remediation. However, one concern is the deterioration of barrier material performance due to pore clogging. This study sought to quantify the effect of pore clogging on the alteration of the physical porous architecture of two novel potential PRB materials (clinoptilolite and calcified seaweed) using image analysis of SEM-derived images. Results after a water treatment contaminated with heavy metals over periods of up to 10 months identified a decrease in porosity from c. 22% to c. 15% for calcified seaweed and from c. 22% to c. 18% for clinoptilolite. Porosity was reduced by as much as 37% in a calcified seaweed column that clogged. The mean pore size (2D) of both materials slightly decreased after water treatment with c. 11% reduction in calcified seaweed and c. 7% reduction in clinoptilolite. An increase in the proportion of crack-shaped pores was observed in both materials after the contaminated water treatment, most noticeably in the bottom of columns where contaminated water first reacted with the material. The distribution of pores (within a given image) derived from the distance transform indicated the largest morphological differences in materials was recorded in calcified seaweed columns, which is likely to impact significantly on their performance as barrier materials. The magnitude of porosity reduction over a short time period in relation to predicted barrier longevity suggest these and similar materials may be unsuited for barrier installation in their present form.

14 CFR 23.691 - Artificial stall barrier system.

Code of Federal Regulations, 2012 CFR

2012-01-01

... AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.691 Artificial stall barrier system. If the function of an artificial stall... downward pitching control will be provided must be established. (b) Considering the plus and minus airspeed...

14 CFR 23.691 - Artificial stall barrier system.

Code of Federal Regulations, 2011 CFR

2011-01-01

... AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.691 Artificial stall barrier system. If the function of an artificial stall... downward pitching control will be provided must be established. (b) Considering the plus and minus airspeed...

14 CFR 23.691 - Artificial stall barrier system.

Code of Federal Regulations, 2013 CFR

2013-01-01

... AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.691 Artificial stall barrier system. If the function of an artificial stall... downward pitching control will be provided must be established. (b) Considering the plus and minus airspeed...

14 CFR 23.691 - Artificial stall barrier system.

Code of Federal Regulations, 2010 CFR

2010-01-01

... AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.691 Artificial stall barrier system. If the function of an artificial stall... downward pitching control will be provided must be established. (b) Considering the plus and minus airspeed...

14 CFR 23.691 - Artificial stall barrier system.

Code of Federal Regulations, 2014 CFR

2014-01-01

... AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL, UTILITY, ACROBATIC, AND COMMUTER CATEGORY AIRPLANES Design and Construction Control Systems § 23.691 Artificial stall barrier system. If the function of an artificial stall... downward pitching control will be provided must be established. (b) Considering the plus and minus airspeed...

MODELING HOW A HURRICANE BARRIER IN NEW BEDFORD HARBOR, MASSACHUSETTS, AFFECTS THE HYDRODYNAMICS AND RESIDENCE TIMES

EPA Science Inventory

Two-dimensional hydrodynamic and transport models were used to simulate tidal and subtidal circulation, residence times, and the longitudinal distributions of conservative constituents in New Bedford Harbor, Massachusetts, before and after a hurricane barrier was constructed. The...

Long-Term Capacity of Plant Mulch to Remediate Trichloroethylene in Groundwater

EPA Science Inventory

Passive reactive barriers are commonly used to treat groundwater that is contaminated with chlorinated solvents such as trichloroethylene (TCE). A number of passive reactive barriers have been constructed with plant mulch as the reactive medium. The TCE is removed in these barr...

Architectural Barriers to the Physically Disabled.

ERIC Educational Resources Information Center

Kirkland, Sue-Anne

Presented is evidence on the increasing need to plan for the accommodation of the physically handicapped in the design and construction of present and future public buildings and transportation facilities in Canada. Terms such as "architectural barriers" and "disability" are defined. Statistics on disability incidence in Canada…

The effects of stream channelization on bottom dwelling organisms : phase 1 report : 1974 construction season.

DOT National Transportation Integrated Search

1975-01-01

Two streams being channelized under Department contracts have been monitored since June 1974. Suspended solids, flow, rainfall and benthic population measurements have been obtained at various times for each stream. At present, all but the benthic po...

Riparian forest communities of the lower Kaskaskia River bottoms

Treesearch

Susan P. Romano; James J. Zaczek; Karl W. J. Williard; Sara Baer; Andrew D. Carver; Jean C. Mangun

2003-01-01

Hydrologic alterations due to dam construction may have altered the floodplain ecology of the Lower Kaskaskia River. Seven forest communities within the study site were identified. Floodplain communities include Acer negundo-Celtis occidentalis-Acer saccharinum, Acer saccharinum-Acer negundo, and Celtis occidentalis-Ulmus americana...

Design high water clearances for highway pavements : [executive summary].

DOT National Transportation Integrated Search

2008-01-01

The majority of state roads in Florida are built using asphalt concrete surfaces. They are constructed in layers. The bottom layer consists of the native soil. The top layer is the surface course, or pavement. It is built upon one or more intermediat...

Re-construction of action awareness depends on an internal model of action-outcome timing.

PubMed

Stenner, Max-Philipp; Bauer, Markus; Machts, Judith; Heinze, Hans-Jochen; Haggard, Patrick; Dolan, Raymond J

2014-04-01

The subjective time of an instrumental action is shifted towards its outcome. This temporal binding effect is partially retrospective, i.e., occurs upon outcome perception. Retrospective binding is thought to reflect post-hoc inference on agency based on sensory evidence of the action - outcome association. However, many previous binding paradigms cannot exclude the possibility that retrospective binding results from bottom-up interference of sensory outcome processing with action awareness and is functionally unrelated to the processing of the action - outcome association. Here, we keep bottom-up interference constant and use a contextual manipulation instead. We demonstrate a shift of subjective action time by its outcome in a context of variable outcome timing. Crucially, this shift is absent when there is no such variability. Thus, retrospective action binding reflects a context-dependent, model-based phenomenon. Such top-down re-construction of action awareness seems to bias agency attribution when outcome predictability is low. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Re-construction of action awareness depends on an internal model of action-outcome timing

PubMed Central

Stenner, Max-Philipp; Bauer, Markus; Machts, Judith; Heinze, Hans-Jochen; Haggard, Patrick; Dolan, Raymond J.

2014-01-01

The subjective time of an instrumental action is shifted towards its outcome. This temporal binding effect is partially retrospective, i.e., occurs upon outcome perception. Retrospective binding is thought to reflect post-hoc inference on agency based on sensory evidence of the action – outcome association. However, many previous binding paradigms cannot exclude the possibility that retrospective binding results from bottom-up interference of sensory outcome processing with action awareness and is functionally unrelated to the processing of the action – outcome association. Here, we keep bottom-up interference constant and use a contextual manipulation instead. We demonstrate a shift of subjective action time by its outcome in a context of variable outcome timing. Crucially, this shift is absent when there is no such variability. Thus, retrospective action binding reflects a context-dependent, model-based phenomenon. Such top-down re-construction of action awareness seems to bias agency attribution when outcome predictability is low. PMID:24555983

Using Frozen Barriers for Containment of Contaminants

DTIC Science & Technology

2017-09-21

barriers are constructed of grout slurry and plastic or steel sheet pilings. Circumferential barriers can be used to completely enclose a source of...2.1.1 Slurry walls A soil-bentonite slurry trench cutoff wall (slurry wall) is excavated and backfilled with grout, cement , or soil-bentonite...installation requires a mixing area, and there is a substantial amount of excavation and the need to dispose of spoil. The advantages of cement -based

Physical inactivity is associated with low self efficacy and social support among patients with hypertension in Nigeria.

PubMed

Idowu, O A; Adeniyi, A F; Atijosan, O J; Ogwumike, O O

2013-06-01

BACKGROUND Physical inactivity is a major factor in the development of many chronic illnesses, including hypertension. Evidence highlighting links among physical activity participation and psychosocial constructs such as self efficacy, social support and perceived barriers among hypertensive patients in the Nigerian population is scarce. This study explored the associations between physical activity and each of self efficacy, social support and perceived barriers. METHODS Two hundred and twelve patients receiving treatment in two tertiary health institutions located in Ekiti State, Nigeria were surveyed cross-sectionally. Physical activity level, self efficacy, social support and perceived barriers were measured with the International Physical Activity Questionnaire, Exercise Self-Efficacy Scale, Medical Outcomes Social Support Scale and Exercise Benefits and Barrier Scale respectively. RESULTS Level of physical activity was significantly associated with self efficacy (r(s) = 0.67, p < 0.01, = 0.45) and social support (r(s) = 0.80, p < 0.01, = 0.64), with most participants (56.1%) being physically inactive. However, no association was found between physical activity level and perceived barriers (r(s) = 0.07, p > 0.01, = 0.005). CONCLUSION Most of the hypertensive patients presented with low levels of physical activity. Physical activity was associated with psychosocial constructs including self efficacy and social support but not with perceived barriers.

Variations of the ionospheric parameters and vertical electron density distribution at the northern edge of the EIA from 2010 to 2015 along 95°E and comparison with the IRI-2012

NASA Astrophysics Data System (ADS)

Kalita, Bitap Raj; Bhuyan, Pradip Kumar

2017-07-01

The vertical electron density profiles over Dibrugarh (27.5°N, 95°E, 43° dip) a low mid latitude station normally located at the northern edge of the EIA for the period of July 2010 till October 2015 are constructed from the measured bottom side profiles and ionosonde-GPS TEC assisted Topside Sounder Model (TSM) topside profiles. The bottom side density profiles are obtained by using POLAN on the manually scaled ionograms. The topside is constructed by the modified ionosonde assisted TSM model (TaP-TSM assisted by POLAN) which is integrated with POLAN for the first time. The reconstructed vertical profile is compared with the IRI predicted density profile and the electron density profile obtained from the COSMIC/FORMOSAT radio occultation measurements over Dibrugarh. The bottom side density profiles are fitted to the IRI bottom side function to obtain best-fit bottom side thickness parameter B0 and shape parameter B1. The temporal and solar activity variation of the B-parameters over Dibrugarh are investigated and compared to those predicted by IRI-2012 model with ABT-2009 option. The bottom side thickness parameter B0 predicted by the IRI model is found to be similar to the B0 measured over Dibrugarh in the night time and the forenoon hours. Differences are observed in the early morning and the afternoon period. The IRI doesn't reproduce the morning collapse of B0 and overestimates the B0 over Dibrugarh in the afternoon period, particularly in summer and equinox. The IRI model predictions are closest to the measured B0 in the winter of low solar activity. The B0 over Dibrugarh is found to increase by about 15% with solar activity during the period of study encompassing almost the first half of solar cycle 24 but solar activity effect was not observed in the B1 parameter. The topside profile obtained from TaP profiler is thicker than the IRI topside in equinox from afternoon to sunrise period but is similar to the IRI in summer daytime. The differences in the bottom side may be attributed to the non-inclusion of ground measurements from 90°E to 100°E longitude in the ABT-2009 model while differences in the topside could be due the non-uniform longitudinal distribution of topside sounder profiles data and the stronger fountain effect in this longitude.

On Suspended matter grain size in Baltic sea

NASA Astrophysics Data System (ADS)

Bubnova, Ekaterina; Sivkov, Vadim; Zubarevich, Victor

2016-04-01

Suspended matter grain size data were gathered during the 25th research vessel "Akademik Mstislav Keldysh" cruise (1991, September-October). Initial quantitative data were obtained with a use of the Coulter counter and subsequently modified into volume concentrations (mm3/l) for size intervals. More than 80 samples from 15 stations were analyzed (depth range 0-355 m). The main goal of research was to illustrate the spatial variability of suspended matter concentration and dispersion in Baltic Sea. The mutual feature of suspended matter grain size distribution is the logical rise of particle number along with descending of particle's size. Vertical variability of grain size distribution was defined by Baltic Sea hydrological structure, including upper mixed layer - from the surface to the thermocline - with 35 m thick, cold intermediate layer - from the thermocline to the halocline- and bottom layer, which lied under the halocline. Upper layer showed a rise in total suspended matter concentration (up to 0.6 mm3/l), while cold intermediate level consisted of far more clear water (up to 0.1 mm3/l). Such a difference is caused by the thermocline boarding role. Meanwhile, deep bottom water experienced surges in suspended matter concentration owing to the nepheloid layer presence and "liquid bottom" effect. Coastal waters appeared to have the highest amount of particles (up to 5.0 mm3/l). Suspended matter grain size distribution in the upper mixed layer revealed a peak of concentration at 7 μ, which can be due to autumn plankton bloom. Another feature in suspended matter grain size distribution appeared at the deep layer below halocline, where both O2 and H2S were observed and red/ox barrier is. The simultaneous presence of Fe and Mn (in solutions below red/ox barrier) and O2 leads to precipitation of oxyhydrates Fe and Mn and grain size distribution graph peaking at 4.5 μ.

Searching for needles in a haystack: identifying innovations to prevent MSDs in the construction sector.

PubMed

Kramer, Desre M; Bigelow, Philip L; Carlan, Niki; Wells, Richard P; Garritano, Enzo; Vi, Peter; Plawinski, Marek

2010-07-01

This study identified innovations that could potentially reduce the risk of MSDs in the construction sector. The action research approach was based on a collaborative model of researchers working with workplace representatives. We searched for innovations being used by construction companies. From a potential database of 125 innovations, the study focused on 20 innovations that varied in their penetration into worksites in the geographical area, represented a variety of trades, and were a cross-section of tools and work organizational processes. It examined the attributes of the innovations, and the barriers to their adoption. The analysis was based on observations of workers, surveys of workers and construction-safety consultants, and company interviews. The study found that innovations were adopted by companies for multiple advantages including productivity and quality, but not necessarily ability to reduce MSD risks, their non-complexity, and cost. The major barriers for adoption were the traditional culture of the construction sector rather than financial ones. Copyright 2010 Elsevier Ltd. All rights reserved.

A new insight into diffusional escape from a biased cylindrical trap

NASA Astrophysics Data System (ADS)

Berezhkovskii, Alexander M.; Dagdug, Leonardo; Bezrukov, Sergey M.

2017-09-01

Recent experiments with single biological nanopores, as well as single-molecule fluorescence spectroscopy and pulling studies of protein and nucleic acid folding raised a number of questions that stimulated theoretical and computational investigations of barrier crossing dynamics. The present paper addresses a closely related problem focusing on trajectories of Brownian particles that escape from a cylindrical trap in the presence of a force F parallel to the cylinder axis. To gain new insights into the escape dynamics, we analyze the "fine structure" of these trajectories. Specifically, we divide trajectories into two segments: a looping segment, when a particle unsuccessfully tries to escape returning to the trap bottom again and again, and a direct-transit segment, when it finally escapes moving without touching the bottom. Analytical expressions are derived for the Laplace transforms of the probability densities of the durations of the two segments. These expressions are used to find the mean looping and direct-transit times as functions of the biasing force F. It turns out that the force-dependences of the two mean times are qualitatively different. The mean looping time monotonically increases as F decreases, approaching exponential F-dependence at large negative forces pushing the particle towards the trap bottom. In contrast to this intuitively appealing behavior, the mean direct-transit time shows rather counterintuitive behavior: it decreases as the force magnitude, |F|, increases independently of whether the force pushes the particles to the trap bottom or to the exit from the trap, having a maximum at F = 0.

Barriers and facilitators to HPV vaccination in primary care practices: a mixed methods study using the Consolidated Framework for Implementation Research.

PubMed

Garbutt, Jane M; Dodd, Sherry; Walling, Emily; Lee, Amanda A; Kulka, Katharine; Lobb, Rebecca

2018-05-07

In the United States, the effective, safe huma papilloma virus (HPV) vaccine is underused and opportunities to prevent cancer continue to be missed. National guidelines recommend completing the 2-3 dose HPV vaccine series by age 13, well before exposure to the sexually transmitted virus. Accurate characterization of the facilitators and barriers to full implementation of HPV vaccine recommendations in the primary care setting could inform effective implementation strategies. We used the Consolidated Framework for Implementation Research (CFIR) to systematically investigate and characterize factors that influence HPV vaccine use in 10 primary care practices (16 providers) using a concurrent mixed methods design. The CFIR was used to guide collection and analysis of qualitative data collected through in-person semi-structured interviews with the primary care providers. We analyzed HPV vaccine use with data abstracted from medical charts. Constructs that most strongly influenced vaccine use were identified by integrating the qualitative and quantitative data. Of the 72 CFIR constructs assessed, seven strongly distinguished and seven weakly distinguished between providers with higher versus lower HPV vaccine coverage. The majority of strongly distinguishing constructs were facilitators and were related to characteristics of the providers (knowledge and beliefs; self-efficacy; readiness for change), their perception of the intervention (relative advantage of vaccinating younger vs. older adolescents), and their process to deliver the vaccine (executing). Additional weakly distinguishing constructs that were facilitators were from outer setting (peer pressure; financial incentives), inner setting (networks and communications and readiness for implementation) and process (planning; engaging, and reflecting and evaluating). Two strongly distinguishing constructs were barriers to use, one from the intervention (adaptability of the age of initiation) and the other from outer setting (patient needs and resources). Using CFIR to systematically examine the use of this vaccine in independent primary care practices enabled us to identify facilitators and barriers at the provider, interpersonal and practice level that need to be addressed in future efforts to increase vaccine use in such settings. Our findings suggest that implementation strategies that target the provider and help them to address multi-level barriers to HPV vaccine use merit further investigation.

RESIDENTIAL RADON RESISTANT CONSTRUCTION FEATURE SELECTION SYSTEM

EPA Science Inventory

The report describes a proposed residential radon resistant construction feature selection system. The features consist of engineered barriers to reduce radon entry and accumulation indoors. The proposed Florida standards require radon resistant features in proportion to regional...

Toward Nucleating the Concept of the Water Resource Recovery Facility (WRRF): Perspective from the Principal Actors.

PubMed

Coats, Erik R; Wilson, Patrick I

2017-04-18

Wastewater resource recovery has been advocated for decades; necessary structural pathways were long-ago articulated, and established and emerging technologies exist. Nevertheless, broad wastewater valorization remains elusive. In considering implementation barriers, the argument is made that decision-makers focus on avoiding permit violations and negative publicity by embracing a conservative/safe approach-seemingly ignoring research on economic/environmental benefits. Conversely positing that economics is a primary barrier, we investigated, characterized, and described nontechnical socio-political barriers to realizing wastewater resource recovery. Principal actors in the Pacific NW region of the U.S. (representing a progressive populace facing stringent water quality regulations) were interviewed. Results revealed that economics were, indeed, the primary barrier to implementation/expansion of the WRRF concept. Consistent throughout interviews was a prevalent sense that the "cost of doing something (different)" was a principal consideration in resource recovery actions/policies. Moreover, "economics drives decisions," and "95% the bottom line is money. Show return on investment, it will get people's attention." Who pays was also a concern: "Government isn't going to pay. The states and Federal government won't give any grants, and we can't raise rates." Applying business case evaluations was seen as a pathway to actualizing resource recovery. Most encouragingly, the consensus was that resource recovery is a necessary future paradigm, and that real barriers are surmountable.

A collapsible trap for capturing ruffe

USGS Publications Warehouse

Edwards, Andrew J.; Czypinski, Gary D.; Selgeby, James H.

1998-01-01

A modified version of the Windermere trap was designed, constructed, and tested for its effectiveness in capturing ruffe Gymnocephalus cernuus. The inexpensive, lightweight, collapsible trap was easily deployed and retrieved from a small boat. Field tests conducted at the St. Louis River estuary in western Lake Superior in spring 1995 and 1996 indicated that the trap was effective in capturing ruffe. Proportions of the ruffe in trap and bottom trawl catches were similar in 1995 and 1996. This trap could be a useful tool in surveillance, monitoring, or control programs for ruffe or similar species, either to augment existing sampling programs or especially in situations where gillnetting or bottom trawling are not feasible.

Purpose-driven biomaterials research in liver-tissue engineering.

PubMed

Ananthanarayanan, Abhishek; Narmada, Balakrishnan Chakrapani; Mo, Xuejun; McMillian, Michael; Yu, Hanry

2011-03-01

Bottom-up engineering of microscale tissue ("microtissue") constructs to recapitulate partially the complex structure-function relationships of liver parenchyma has been realized through the development of sophisticated biomaterial scaffolds, liver-cell sources, and in vitro culture techniques. With regard to in vivo applications, the long-lived stem/progenitor cell constructs can improve cell engraftment, whereas the short-lived, but highly functional hepatocyte constructs stimulate host liver regeneration. With regard to in vitro applications, microtissue constructs are being adapted or custom-engineered into cell-based assays for testing acute, chronic and idiosyncratic toxicities of drugs or pathogens. Systems-level methods and computational models that represent quantitative relationships between biomaterial scaffolds, cells and microtissue constructs will further enable their rational design for optimal integration into specific biomedical applications. Copyright © 2010 Elsevier Ltd. All rights reserved.

Problems in characterizing barrier performance

NASA Technical Reports Server (NTRS)

Jordan, Harry F.

1988-01-01

The barrier is a synchronization construct which is useful in separating a parallel program into parallel sections which are executed in sequence. The completion of a barrier requires cooperation among all executing processes. This requirement not only introduces the wait for the slowest process delay which is inherent in the definition of the synchronization, but also has implications for the efficient implementation and measurement of barrier performance in different systems. Types of barrier implementation and their relationship to different multiprocessor environments are described. Then the problem of measuring the performance of barrier implementations on specific machine architecture is discussed. The fact that the barrier synchronization requires the cooperation of all processes makes the problem of performance measurement similarly global. Making non-intrusive measurements of sufficient accuracy can be tricky on systems offering only rudimentary measurement tools.

A tunable acoustic barrier based on periodic arrays of subwavelength slits

NASA Astrophysics Data System (ADS)

Rubio, Constanza; Uris, Antonio; Candelas, Pilar; Belmar, Francisco; Gomez-Lozano, Vicente

2015-05-01

The most usual method to reduce undesirable enviromental noise levels during its transmission is the use of acoustic barriers. A novel type of acoustic barrier based on sound transmission through subwavelength slits is presented. This system consists of two rows of periodic repetition of vertical rigid pickets separated by a slit of subwavelength width and with a misalignment between them. Here, both the experimental and the numerical analyses are presented. The acoustic barrier proposed can be easily built and is frequency tunable. The results demonstrated that the proposed barrier can be tuned to mitigate a band noise without excesive barrier thickness. The use of this system as an environmental acoustic barrier has certain advantages with regard to the ones currently used both from the constructive and the acoustical point of view.

Barriers and dispersal surfaces in minimum-time interception

NASA Technical Reports Server (NTRS)

Rajan, N.; Ardema, M. D.

1982-01-01

Minimum time interception of a target moving in a horizontal plane is analyzed as a one-player differential game. Dispersal points and points on the barrier are located for a class of pursuit evasion and interception problems. These points are determined by constructing cross sections of the isochrones and hence obtaining the barrier, dispersal, and control level surfaces. The game solution maps the controls as a function of the state within the capture region.

Green noise wall construction and evaluation.

DOT National Transportation Integrated Search

2011-09-01

This report details the research performed under Phase I of a research study titled Green Noise Wall Construction and Evaluation that looks into the feasibility of using green noise barriers as a noise mitigation option in Ohio. This phase incl...

Abiotic and Biotic Transformation of TCE under Sulfate Reducing Conditions: the Role of Spatial Heterogeneity

EPA Science Inventory

At a number of sites in the USA, passive reactive barriers built with shredded plant mulch have been constructed to treat ground water contaminated with TCE. These barriers are called biowalls because anaerobic biodegradation of the plant mulch is expected to provide substrates...

41 CFR 102-76.65 - What standards must facilities subject to the Architectural Barriers Act meet?

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false What standards must... Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 76-DESIGN AND CONSTRUCTION Architectural Barriers Act § 102-76.65 What standards...

41 CFR 102-76.65 - What standards must facilities subject to the Architectural Barriers Act meet?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false What standards must... Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 76-DESIGN AND CONSTRUCTION Architectural Barriers Act § 102-76.65 What standards...

41 CFR 102-76.65 - What standards must facilities subject to the Architectural Barriers Act meet?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false What standards must... Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 76-DESIGN AND CONSTRUCTION Architectural Barriers Act § 102-76.65 What standards...

41 CFR 102-76.65 - What standards must facilities subject to the Architectural Barriers Act meet?

Code of Federal Regulations, 2012 CFR

2012-01-01

... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false What standards must... Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 76-DESIGN AND CONSTRUCTION Architectural Barriers Act § 102-76.65 What standards...

On a Class of Hairy Square Barriers and Gamow Vectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fernandez-Garcia, N.

The second order Darboux-Gamow transformation is applied to deform square one dimensional barriers in non-relativistic quantum mechanics. The initial and the new 'hairy' potentials have the same transmission probabilities (for the appropriate parameters). In general, new Gamow vectors are constructed as Darboux deformations of the initial ones.

46 CFR 154.460 - Design criteria.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 5 2011-10-01 2011-10-01 false Design criteria. 154.460 Section 154.460 Shipping COAST... SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Secondary Barrier § 154.460 Design criteria. At static angles of heel up through 30°, a secondary barrier must (a...

A Tracer Test to Characterize Treatment of TCE in a Permeable Reactive Barrier

EPA Science Inventory

A tracer test was conducted to characterize the flow of ground water surrounding a permeable reactive barrier constructed with plant mulch (a biowall) at the OU-1 site on Altus Air Force Base, Oklahoma. This biowall is intended to intercept and treat ground water contaminated by ...

41 CFR 102-76.65 - What standards must facilities subject to the Architectural Barriers Act meet?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What standards must... Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 76-DESIGN AND CONSTRUCTION Architectural Barriers Act § 102-76.65 What standards...

Department Chairs as Change Agents: Leading Change in Resistant Environments

ERIC Educational Resources Information Center

Gaubatz, Julie A.; Ensminger, David C.

2017-01-01

Change process research often discusses barriers that impede organizational change (e.g., Banta, 1997; Cavacuiti and Locke, 2013; Mutchler, 1990; Stewart et al., 2012); however, no empirical research has addressed how behaviors established in leadership models counteract these barriers. This study explored these two interconnected constructs of…

Transformation of Reactive Iron Minerals in a Permeable Reactive Barrier (Biowall) Used to Treat TCE in Groundwater

EPA Science Inventory

Abstract: Iron and sulfur reducing conditions are generally created in permeable reactive barrier (PRB) systems constructed for groundwater treatment, which usually leads to formation of iron sulfide phases. Iron sulfides have been shown to play an important role in degrading ch...

Barrier or Benefit? Emotion in Life-Career Design

ERIC Educational Resources Information Center

Hartung, Paul J.

2011-01-01

Emotion permeates human life, yet receives little attention in career theory and intervention. Long seen as a barrier to avoid, recent conceptual and empirical work indicate that emotion benefits human behavior and development. Advances in the interdisciplinary science of emotion support examining the construct across differential, developmental,…

Acoustical characterization and parameter optimization of polymeric noise control materials

NASA Astrophysics Data System (ADS)

Homsi, Emile N.

2003-10-01

The sound transmission loss (STL) characteristics of polymer-based materials are considered. Analytical models that predict, characterize and optimize the STL of polymeric materials, with respect to physical parameters that affect performance, are developed for single layer panel configuration and adapted for layered panel construction with homogenous core. An optimum set of material parameters is selected and translated into practical applications for validation. Sound attenuating thermoplastic materials designed to be used as barrier systems in the automotive and consumer industries have certain acoustical characteristics that vary in function of the stiffness and density of the selected material. The validity and applicability of existing theory is explored, and since STL is influenced by factors such as the surface mass density of the panel's material, a method is modified to improve STL performance and optimize load-bearing attributes. An experimentally derived function is applied to the model for better correlation. In-phase and out-of-phase motion of top and bottom layers are considered. It was found that the layered construction of the co-injection type would exhibit fused planes at the interface and move in-phase. The model for the single layer case is adapted to the layered case where it would behave as a single panel. Primary physical parameters that affect STL are identified and manipulated. Theoretical analysis is linked to the resin's matrix attribute. High STL material with representative characteristics is evaluated versus standard resins. It was found that high STL could be achieved by altering materials' matrix and by integrating design solution in the low frequency range. A suggested numerical approach is described for STL evaluation of simple and complex geometries. In practice, validation on actual vehicle systems proved the adequacy of the acoustical characterization process.

Ultralow-power complementary metal-oxide-semiconductor inverters constructed on Schottky barrier modified nanowire metal-oxide-semiconductor field-effect-transistors.

PubMed

Ma, R M; Peng, R M; Wen, X N; Dai, L; Liu, C; Sun, T; Xu, W J; Qin, G G

2010-10-01

We show that the threshold voltages of both n- and p-channel metal-oxide-semiconductor field-effect-transistors (MOSFETs) can be lowered to close to zero by adding extra Schottky contacts on top of nanowires (NWs). Novel complementary metal-oxide-semiconductor (CMOS) inverters are constructed on these Schottky barrier modified n- and p-channel NW MOSFETs. Based on the high performances of the modified n- and p-channel MOSFETs, especially the low threshold voltages, the as-fabricated CMOS inverters have low operating voltage, high voltage gain, and ultra-low static power dissipation.

[Sensory stimulation: new apparatus for demented men].

PubMed

de Groot, M D; Molenbroek, J F

2001-10-01

In order to study the feasibility of new sensorily stimulating material for elderly demented men, their behaviour was observed while the material was handed over to them. The newly developed materials consisted of five different constructions, i.e. a mirrorbox, a simple hand-operated stroboscope, a spring-operated ball for ringing a bell, two rotating wooden cogwheels, and a box having a sandpaper bottom of different grains causing a tactile contrast. In their verbal and nonverbal responses the demented men showed clear signs of interest in the constructions and the materials. The seven participating men showed much interest in materials made of wood and metal, and in the working of the constructions. The different constructions and materials could be combined into one complete 'snoezelproduct'.

Capacitance and conductance-frequency characteristics of In-pSi Schottky barrier diode

NASA Astrophysics Data System (ADS)

Dhimmar, J. M.; Desai, H. N.; Modi, B. P.

2015-06-01

The Schottky barrier height (SBH) values have been calculated by using the reverse bias capacitance-voltage (C-V) characteristics at temperature range of 120-360K. The forward bias capacitance-frequency (C-f) and conductance- frequency (G-f) measurement of In-pSi SBD have been carried out from 0-1.0 V with a step up 0.05 V whereby the energy distribution of the interface state has been determined from the forward bias I-V data taking the bias dependence of the effective barrier height and series resistance (RS) into account. The high value of ideality factor (n=2.12) was attributing to high density of interface states and interfacial oxide layer at metal semiconductor interface. The interface state density (NSS) shows a decrease with bias from bottom of conduction band toward the mid gap. In order to examine frequency dependence NSS, RS, C-V and G(ω)/ω-f measurement of the diode were performed at room temperature in the frequency range of 100Hz-100KHz. Experimental result confirmed that there is an influence in the electrical characteristic of Schottky diode.

Integration of perovskite oxide dielectrics into complementary metal-oxide-semiconductor capacitor structures using amorphous TaSiN as oxygen diffusion barrier

NASA Astrophysics Data System (ADS)

Mešić, Biljana; Schroeder, Herbert

2011-09-01

The high permittivity perovskite oxides have been intensively investigated for their possible application as dielectric materials for stacked capacitors in dynamic random access memory circuits. For the integration of such oxide materials into the CMOS world, a conductive diffusion barrier is indispensable. An optimized stack p++-Si/Pt/Ta21Si57N21/Ir was developed and used as the bottom electrode for the oxide dielectric. The amorphous TaSiN film as oxygen diffusion barrier showed excellent conductive properties and a good thermal stability up to 700 °C in oxygen ambient. The additional protective iridium layer improved the surface roughness after annealing. A 100-nm-thick (Ba,Sr)TiO3 film was deposited using pulsed laser deposition at 550 °C, showing very promising properties for application; the maximum relative dielectric constant at zero field is κ ≈ 470, and the leakage current density is below 10-6 A/cm2 for fields lower then ± 200 kV/cm, corresponding to an applied voltage of ± 2 V.

Ab initio study of the mechanism of bottom-up synthesis of graphene nanoribbons

NASA Astrophysics Data System (ADS)

Xiao, Zhongcan; Ma, Chuanxu; Zhang, Honghai; Liang, Liangbo; Huang, Jingsong; Lu, Wenchang; Hong, Kunlun; Li, An-Ping; Bernholc, Jerry

Graphene nanoribbons (GNRs) can be fabricated with atomic precision by using molecular precursors deposited on a metal substrate, and potentially form the basis for future molecular-scale electronics. The precursor molecules are first annealed to form a polymer, and further annealing at a higher temperature leads to the formation of a GNR. We systematically study the reaction pathways of this cyclodehydrogenation process, using density functional theory and the nudged elastic band method. We find that the Au substrate reduces the reaction barriers for key steps in the cyclodehydrogenation process: cyclization, hydrogen migration and desorption. Furthermore, our calculations explain recent experiments showing that an STM-tip can induce local polymer-to-GNR transition, which can be used to fabricate atomically precise heterojunctions: at a negative bias, the STM tip injects excess holes into the polymer HOMO state, lowering the energy barrier in agreement with Woodward-Hoffmann rules. At a positive bias, when excess electrons are injected into the LUMO state, the energy barrier is not significantly lowered and the transition is not observed.

29 CFR 1926.152 - Flammable liquids.

Code of Federal Regulations, 2013 CFR

2013-07-01

... tank, unless control valves and their connections to the tank are of a type designed to prevent... storage cabinets shall be constructed in the following manner, or equivalent: The bottom, sides, and top... extinguishing system is provided, the system shall be designed and installed in an approved manner. Openings to...

29 CFR 1926.152 - Flammable liquids.

Code of Federal Regulations, 2012 CFR

2012-07-01

... tank, unless control valves and their connections to the tank are of a type designed to prevent... storage cabinets shall be constructed in the following manner, or equivalent: The bottom, sides, and top... extinguishing system is provided, the system shall be designed and installed in an approved manner. Openings to...

29 CFR 1926.152 - Flammable and combustible liquids.

Code of Federal Regulations, 2010 CFR

2010-07-01

... access way to permit approach of fire control apparatus. (3) The storage area shall be graded in a manner... to permit approach of fire control apparatus. (5) Storage areas shall be kept free of weeds, debris... wooden storage cabinets shall be constructed in the following manner, or equivalent: The bottom, sides...

Neutrino astrophysics experiments beneath the sea and ice.

PubMed

Halzen, Francis

2007-01-05

Neutrino astronomy beyond the Sun was first imagined in the late 1950s. A neutrino detector at the bottom of Lake Baikal, the deployment of detectors in the Mediterranean Sea, and the construction of a kilometer-scale neutrino telescope at the South Pole exemplify current efforts to realize this dream.

18 CFR 35.25 - Construction work in progress.

Code of Federal Regulations, 2012 CFR

2012-04-01

... of pollution produced by the power plant, but does not include any facility that reduces pollution by... oil or coal burners, soot blowers, bottom ash removal systems and concomitant air pollution control..., which facility would not be necessary if the plant continued to burn gas or oil. (4) Pollution control...

18 CFR 35.25 - Construction work in progress.

Code of Federal Regulations, 2013 CFR

2013-04-01

... of pollution produced by the power plant, but does not include any facility that reduces pollution by... oil or coal burners, soot blowers, bottom ash removal systems and concomitant air pollution control..., which facility would not be necessary if the plant continued to burn gas or oil. (4) Pollution control...

18 CFR 35.25 - Construction work in progress.

Code of Federal Regulations, 2010 CFR

2010-04-01

... of pollution produced by the power plant, but does not include any facility that reduces pollution by... oil or coal burners, soot blowers, bottom ash removal systems and concomitant air pollution control..., which facility would not be necessary if the plant continued to burn gas or oil. (4) Pollution control...

18 CFR 35.25 - Construction work in progress.

Code of Federal Regulations, 2011 CFR

2011-04-01

... public utility applicant to provide for separate customer groups or provide for a rate design... oil or coal burners, soot blowers, bottom ash removal systems and concomitant air pollution control..., which facility would not be necessary if the plant continued to burn gas or oil. (4) Pollution control...

18 CFR 35.25 - Construction work in progress.

Code of Federal Regulations, 2014 CFR

2014-04-01

... public utility applicant to provide for separate customer groups or provide for a rate design... oil or coal burners, soot blowers, bottom ash removal systems and concomitant air pollution control..., which facility would not be necessary if the plant continued to burn gas or oil. (4) Pollution control...

A "Bottom-Up" Approach to Food Web Construction

ERIC Educational Resources Information Center

Demetriou, Dorita; Korfiatis, Konstantinos; Constantinou, Constantinos

2009-01-01

The ability to comprehend trophic (nutritional) relationships and food web dynamics is an essential part of environmental literacy. However, students face severe difficulties in grasping the variety of causal patterns in food webs. We propose a curriculum for comprehending trophic relations in elementary school. The curriculum allows students to…

29 CFR 1926.152 - Flammable and combustible liquids.

Code of Federal Regulations, 2011 CFR

2011-07-01

... access way to permit approach of fire control apparatus. (3) The storage area shall be graded in a manner... to permit approach of fire control apparatus. (5) Storage areas shall be kept free of weeds, debris... wooden storage cabinets shall be constructed in the following manner, or equivalent: The bottom, sides...

Crystal accumulation in the Hanford Waste Treatment Plant high level waste melter. Preliminary settling and resuspension testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fox, K. M.; Fowley, M. D.; Miller, D. H.

2016-05-01

The full-scale, room-temperature Hanford Tank Waste Treatment and Immobilization Plant (WTP) High-Level Waste (HLW) melter riser test system was successfully operated with silicone oil and magnetite particles at a loading of 0.1 vol %. Design and construction of the system and instrumentation, and the selection and preparation of simulant materials, are briefly reviewed. Three experiments were completed. A prototypic pour rate was maintained, based on the volumetric flow rate. Settling and accumulation of magnetite particles were observed at the bottom of the riser and along the bottom of the throat after each experiment. The height of the accumulated layer atmore » the bottom of the riser, after the first pouring experiment, approximated the expected level given the solids loading of 0.1 vol %. More detailed observations of particle resuspension and settling were made during and after the third pouring experiment. The accumulated layer of particles at the bottom of the riser appeared to be unaffected after a pouring cycle of approximately 15 minutes at the prototypic flow rate. The accumulated layer of particles along the bottom of the throat was somewhat reduced after the same pouring cycle. Review of the time-lapse recording showed that some of the settling particles flow from the riser into the throat. This may result in a thicker than expected settled layer in the throat.« less

Shallow Geologic Framework and Geomorphic Evolution of a Paleo-barrier Shoreline, Terrebonne and Timbalier Bay, Louisiana, USA.

NASA Astrophysics Data System (ADS)

Culling, D. P.; Allison, M. A.; Kulp, M. A.; Georgiou, I. Y.; Weathers, H. D., III

2016-12-01

The Louisiana coast is an invaluable asset to the nation's human, economic, and ecological welfare. However, due to the combined effects of coastal erosion, subsidence, and sea level rise, Louisiana is losing on average 25 km2 of its valuable coastal wetlands per year. Terrebonne- Timbalier Bay and the associated Lafourche deltaic lobe headland is a critical section of this coast for wetlands and infrastructure protection and restoration in the State's Master Plan. Historical imagery and bathymetry clearly show the rapid transgression and erosional degradation of both sets of headland-flanking barrier island shorelines due to wave attack and relative sea level rise in the past 150 y. The focus of the present study is a barrier island system: an ocean-fronting modern-barrier shoreline and a paleo-deltaic headland barrier arc inland of the active barrier. The evolution of the modern barrier arc is closely tied to the shallow geologic framework over which it is transgressing, and specifically the sand re-activation capacity of the antecedent geology once erosional forces are introduced. To understand the evolution of these barrier systems and how to address their protection and re-nourishment, it is important to quantify (1) the depositional facies geometry and (2) the volume of sand in these back-barrier sandy lithosomes. Here we present new observations from CHIRP sub-bottom seismic multibeam bathymetry and LIDAR topography, and surface grab and vibracore sampling in an effort to quantify the sediment availability within the underlying geologic framework and reconstruct the geomorphic evolution of these barrier shorelines. Preliminary results show the morphologic expression of antecedent geology, which is evident in seismic and bathymetric patterns, and the presence of near-surface and surface sandy stratigraphy within the back barrier bay. Observations of sandy units agree with results from Kulp et al. (2005), who showed the presence and extent of sandy lithofacies within 3 m of the surface proximal to the Raccoon Pass tidal-inlet. We suggest this sand is an important potential resource for the longevity of proximal sandy barriers as transgression continues; one identified lithesome alone is estimated to contain 5.25 km3 of fine-grained sand.

Etude du comportement hydrogeologique de couvertures avec effet de barriere capillaire faites entierement de materiaux miniers

NASA Astrophysics Data System (ADS)

Kalonji, Alex Kabambi

The acid mining drainage (AMD) generating mine sites must be restored to limit their long-term contamination of the environment. At the end of mining operations, covers with capillary barrier effects (CCBE), generally made of natural materials soils, are used as an oxygen barrier to isolate the tailings that generate acid mining drainage (AMD) from their immediate environment. Due to economic and social acceptability contraints and to the environmental impact of stripping (footprint) of natural soil pits, mining companies are increasingly interested in using non-acid generating waste rock as a substitute for natural soils as base materials to form capillary break layers in covers. The overall objective of this study was to evaluate the hydrogeological behaviour of CCBE made entirely of mining materials (desulphurized tailings from a desulphurization process and non-acid generating waste rock). The specific objectives of this project were : 1) to characterize the hydrogeological properties of waste rock (with truncated size) and desulphurized tailings; 2) to evaluate in laboratory instrumented columns the effectiveness of CCBE made entirely of mining materials; 3) to simulate the column tests using a 1D numerical code to model the fluid (water and gas) flow in the unsaturated media; and 4) to validate with 2D numerical modeling the ability to restore LaRonde tailings impoundment (Agnico Eagle Mines Limited) using a CCBE made of low-sulfide tailings and non-acid generating waste rock. To achieve the objectives, samples of waste rock were collected from Bousquet waste rock pile and tailings from the ore concentration plant before being pumped to the tailings impoundment. Desulphurized tailings with less than 2% S were produced in order to construct a non-reactive CCBE. After the physical, chemical, mineralogical and hydrogeotechnical characterization of cover materials, laboratory physical models of CCBC in instrumented columns were performed. Three configurations were tested. The first two columns had a different waste rock grain size (0-20 mm and 0-50 mm) in their lower coarse layers, and the tailings were introduced at a high solid percent, approximatively 74% (simulating mechanical deposition). The third column also had waste rock with particle size 0-50 mm in its bottom coarse layer, but with tailings placed a lower solid percent, approximatively 55% (simulating hydraulic deposition). The particle size of the coarse waste rock in the top layers was set at 0-50 mm for all three columns. Several cycles of wetting drainage in the three columns were performed. The results of these laboratory investigations in terms of volumetric water content and suction profiles confirm the potential of non-acid generating waste rock to be used in the capillary break layers of CCBE. To assess the long-term performance, several scenarios of numerical modeling were performed using Vadose/W 2007 numerical codes, by Geoslope int. A variation of the depth of the water table and natural and extreme climatic conditions were considered in this parametric study. The results of these predictions confirmed the long-term effectiveness of covers with mine waste rock in capillary break layers. The effectiveness was evaluated in terms of oxygen flux at the interface between the moisture-retaining layer (MRL) and the bottom capillary break layer. Under natural and extreme climatic conditions (two months without infiltration), and a variation of the depth of the water table level from 2 to 6 m, cumulative oxygen flux over a one year period varied between 10.6 and 97.5 g/m 2/year. For extreme climatic conditions, and for the same variation of the depth of the water table, the oxygen flux varied between 14.3 and 117.9 g/m2/year. The highest oxygen flux (117 g/m2/year) was obtained for a water table depth of 6 m under extreme climatic conditions. The influence of the particle size contrast between the water retention layer and the bottom capillary break layer on the oxygen flux was further highlighted using relatively fine and coarse sand in the coarse bottom layer. The numerical modeling results obtained with the coarse sand were almost similar to those obtained with waste rock. In the absence of the strong contrast (when the relatively fine sand was used), the water retention layer was drained and the oxygen flux which reached at the bottom of this layer increased considerably. The water table depth, the grain size, and the hydraulic contrast between the MRL and the bottom capillary break layer (CBL) proved to be the key parameters of the simulated model. In field conditions, CCBE are often inclined, and that this inclination can affect the performance of the cover to control the migration of oxygen. 2D modeling was also performed. The numerical model was built to represent approximatively the case of one of the dams of LaRonde tailings impoundment. Preliminary results show that CCBE made entirely of mining materials are effective even when placed over slopes. The degree of saturation of the two slopes in the numerical model was higher than 85%. The influence of the slope has not significantly affected yet the performance of the cover for the model studied in this thesis. The cumulative oxygen flux over one year at the bottom of the MRL (for horizontal distance of 182 m of the numerical model) are 4031.3g (22.1 g/m2/year) and 4617.7g (25.3 g/m2/year) for natural and extreme climatic conditions respectively. This study confirms that waste rocks have good potential to be used as capillary break materials in the configuration of such CCBE. Thereby, it is suggested that the option of using only mining materials be included in the analysis of the optimal mode of mine reclamation. This project also suggests that good management of the tailings and waste rock produced during mining operations will provide the materials which could then be used to restore the site. More research is recommended to further investigate this reclamation option through field experimental cells. If further research validates the laboratory results at the intermediate scale, the use of mining materials would be considered as an effective option for CCBE used to control post-closure pollution. This scenario could reduce the construction costs while promoting the social acceptability of mining projects by reducing the use of natural soils.

Tailoring the morphology and luminescence of GaN/InGaN core-shell nanowires using bottom-up selective-area epitaxy

NASA Astrophysics Data System (ADS)

Nami, Mohsen; Eller, Rhett F.; Okur, Serdal; Rishinaramangalam, Ashwin K.; Liu, Sheng; Brener, Igal; Feezell, Daniel F.

2017-01-01

Controlled bottom-up selective-area epitaxy (SAE) is used to tailor the morphology and photoluminescence properties of GaN/InGaN core-shell nanowire arrays. The nanowires are grown on c-plane sapphire substrates using pulsed-mode metal organic chemical vapor deposition. By varying the dielectric mask configuration and growth conditions, we achieve GaN nanowire cores with diameters ranging from 80 to 700 nm that exhibit various degrees of polar, semipolar, and nonpolar faceting. A single InGaN quantum well (QW) and GaN barrier shell is also grown on the GaN nanowire cores and micro-photoluminescence is obtained and analyzed for a variety of nanowire dimensions, array pitch spacings, and aperture diameters. By increasing the nanowire pitch spacing on the same growth wafer, the emission wavelength redshifts from 440 to 520 nm, while increasing the aperture diameter results in a ˜35 nm blueshift. The thickness of one QW/barrier period as a function of pitch and aperture diameter is inferred using scanning electron microscopy, with larger pitches showing significantly thicker QWs. Significant increases in indium composition were predicted for larger pitches and smaller aperture diameters. The results are interpreted in terms of local growth conditions and adatom capture radius around the nanowires. This work provides significant insight into the effects of mask configuration and growth conditions on the nanowire properties and is applicable to the engineering of monolithic multi-color nanowire LEDs on a single chip.

A biological approach to assembling tissue modules through endothelial capillary network formation.

PubMed

Riesberg, Jeremiah J; Shen, Wei

2015-09-01

To create functional tissues having complex structures, bottom-up approaches to assembling small tissue modules into larger constructs have been emerging. Most of these approaches are based on chemical reactions or physical interactions at the interface between tissue modules. Here we report a biological assembly approach to integrate small tissue modules through endothelial capillary network formation. When adjacent tissue modules contain appropriate extracellular matrix materials and cell types that support robust endothelial capillary network formation, capillary tubules form and grow across the interface, resulting in assembly of the modules into a single, larger construct. It was shown that capillary networks formed in modules of dense fibrin gels seeded with human umbilical vein endothelial cells (HUVECs) and mesenchymal stem cells (MSCs); adjacent modules were firmly assembled into an integrated construct having a strain to failure of 117 ± 26%, a tensile strength of 2208 ± 83 Pa and a Young's modulus of 2548 ± 574 Pa. Under the same culture conditions, capillary networks were absent in modules of dense fibrin gels seeded with either HUVECs or MSCs alone; adjacent modules disconnected even when handled gently. This biological assembly approach eliminates the need for chemical reactions or physical interactions and their associated limitations. In addition, the integrated constructs are prevascularized, and therefore this bottom-up assembly approach may also help address the issue of vascularization, another key challenge in tissue engineering. Copyright © 2015 John Wiley & Sons, Ltd.

Effect of a multi-layer infection control barrier on the micro-hardness of a composite resin

PubMed Central

HWANG, In-Nam; HONG, Sung-Ok; LEE, Bin-Na; HWANG, Yun-Chan; OH, Won-Mann; CHANG, Hoon-Sang

2012-01-01

Objective The aim of this study was to evaluate the effect of multiple layers of an infection control barrier on the micro-hardness of a composite resin. Material and Methods One, two, four, and eight layers of an infection control barrier were used to cover the light guides of a high-power light emitting diode (LED) light curing unit (LCU) and a low-power halogen LCU. The composite specimens were photopolymerized with the LCUs and the barriers, and the micro-hardness of the upper and lower surfaces was measured (n=10). The hardness ratio was calculated by dividing the bottom surface hardness of the experimental groups by the irradiated surface hardness of the control groups. The data was analyzed by two-way ANOVA and Tukey's HSD test. Results The micro-hardness of the composite specimens photopolymerized with the LED LCU decreased significantly in the four- and eight-layer groups of the upper surface and in the two-, four-, and eight-layer groups of the lower surface. The hardness ratio of the composite specimens was <80% in the eight-layer group. The micro-hardness of the composite specimens photopolymerized with the halogen LCU decreased significantly in the eight-layer group of the upper surface and in the two-, four-, and eight-layer groups of the lower surface. However, the hardness ratios of all the composite specimens photopolymerized with barriers were <80%. Conclusions The two-layer infection control barrier could be used on high-power LCUs without decreasing the surface hardness of the composite resin. However, when using an infection control barrier on the low-power LCUs, attention should be paid so as not to sacrifice the polymerization efficiency. PMID:23138746

Adapting to climate change by water management organisations: Enablers and barriers

NASA Astrophysics Data System (ADS)

Azhoni, Adani; Jude, Simon; Holman, Ian

2018-04-01

Climate change will be particularly experienced though the medium of water. Water organisations, that are managing societal and ecological needs for water, are therefore likely to experience the impact the most. This study reviews the current literature regarding adaptation to climate change by water management organisations and associated barriers. Literature on adaptive capacity is growing and a general consensus is emerging on the determinants of adaptive capacity, although variations exist regarding how it is to be evaluated, enhanced and applied to policy making due to its dynamic, contextual and latent nature. Since adaptive capacity is hard to measure and successful adaptation difficult to define, some studies focus on the existence of adaptation attributes of organisations. Studies reporting successful adaptation are minimal and barriers of adaptation are being discovered as adaptation research transitions into implementation. But the root causes of these barriers are often overlooked and the interconnectedness of the barriers is poorly addressed. Increasingly, combining top-down and bottom-up approaches to adaptation is being recommended due to the limitations of each. However, knowledge regarding how organisations operating at different scales can enhance adaptive capacity of other organisations operating at another scale is lacking due to the few studies of inter-organisational networks across scales. Social networks among actors are recognised as a key factor to enable adaptation. However, network studies generally focus on individual actors and rarely between public agencies/organisations. Moreover, the current literature is inadequate to understand the relationship between adaptation enabling characteristics, barriers and adaptation manifestation. The review demonstrates that research on understanding the emergence and sustenance of barriers is urgently required. Addressing these knowledge gaps will help to improve the design of adaptation strategies, thereby improving the ability of water management to address the ongoing challenges of climate change.

Underground barrier construction apparatus with soil-retaining shield

DOEpatents

Gardner, Bradley M.; Smith, Ann Marie; Hanson, Richard W.; Hodges, Richard T.

1998-01-01

An apparatus for building a horizontal underground barrier by cutting through soil and depositing a slurry, preferably one which cures into a hardened material. The apparatus includes a digging means for cutting and removing soil to create a void under the surface of the ground, a shield means for maintaining the void, and injection means for inserting barrier-forming material into the void. In one embodiment, the digging means is a continuous cutting chain. Mounted on the continuous cutting chain are cutter teeth for cutting through soil and discharge paddles for removing the loosened soil. This invention includes a barrier placement machine, a method for building an underground horizontal containment barrier using the barrier placement machine, and the underground containment system. Preferably the underground containment barrier goes underneath and around the site to be contained in a bathtub-type containment.

Mass production of bulk artificial nacre with excellent mechanical properties.

PubMed

Gao, Huai-Ling; Chen, Si-Ming; Mao, Li-Bo; Song, Zhao-Qiang; Yao, Hong-Bin; Cölfen, Helmut; Luo, Xi-Sheng; Zhang, Fu; Pan, Zhao; Meng, Yu-Feng; Ni, Yong; Yu, Shu-Hong

2017-08-18

Various methods have been exploited to replicate nacre features into artificial structural materials with impressive structural and mechanical similarity. However, it is still very challenging to produce nacre-mimetics in three-dimensional bulk form, especially for further scale-up. Herein, we demonstrate that large-sized, three-dimensional bulk artificial nacre with comprehensive mimicry of the hierarchical structures and the toughening mechanisms of natural nacre can be facilely fabricated via a bottom-up assembly process based on laminating pre-fabricated two-dimensional nacre-mimetic films. By optimizing the hierarchical architecture from molecular level to macroscopic level, the mechanical performance of the artificial nacre is superior to that of natural nacre and many engineering materials. This bottom-up strategy has no size restriction or fundamental barrier for further scale-up, and can be easily extended to other material systems, opening an avenue for mass production of high-performance bulk nacre-mimetic structural materials in an efficient and cost-effective way for practical applications.Artificial materials that replicate the mechanical properties of nacre represent important structural materials, but are difficult to produce in bulk. Here, the authors exploit the bottom-up assembly of 2D nacre-mimetic films to fabricate 3D bulk artificial nacre with an optimized architecture and excellent mechanical properties.

Effects of Geometrical and Flow Rates on the Prediction of Bottom Pressure Coefficients of Tunnel Lift Gate of Dams

NASA Astrophysics Data System (ADS)

Ameen, Sheeraz; Taher, Taha; Ahmed, Thamir M.

2018-06-01

Hydrostatics and hydrodynamics forces are generated and applied on the vertical lift tunnel gates due to the influence of a wide range of dam operating conditions. One of the most important forces is the uplift force resulting from the jet flow issuing below the gate. This force is based mainly upon many hydraulic and geometrical parameters. In this work, the uplift force is studied in terms of bottom pressure coefficient. The investigation is made paying particular attention on the effects of various three discharges and three gate lip angles on values of bottom pressure coefficients in addition to four different tunnel longitudinal slopes whose impact has not been studied in many previous works. Hydraulic model is constructed in this work for the sake of measuring all parameters required for estimating the bottom pressure coefficients, which are all examined against gate openings. The results show that the bottom pressure coefficient is related to the said variables, however, its behaviour and values are not necessary regular with variance of studied variables. The values are seen more significantly related to the flow rates and for some extent to the slopes of tunnel. An attempt by using the nonlinear regression of Statistical package of social sciences (SPSS) is made to set equations relating bottom pressure coefficient with gate openings for several angles of gate lips. The obtained equations are shown in good agreement with the selected cases of experimental results. The results are applicable for design purposes for similar geometrical and flow parameters considered in this study.

Recursive random forest algorithm for constructing multilayered hierarchical gene regulatory networks that govern biological pathways.

PubMed

Deng, Wenping; Zhang, Kui; Busov, Victor; Wei, Hairong

2017-01-01

Present knowledge indicates a multilayered hierarchical gene regulatory network (ML-hGRN) often operates above a biological pathway. Although the ML-hGRN is very important for understanding how a pathway is regulated, there is almost no computational algorithm for directly constructing ML-hGRNs. A backward elimination random forest (BWERF) algorithm was developed for constructing the ML-hGRN operating above a biological pathway. For each pathway gene, the BWERF used a random forest model to calculate the importance values of all transcription factors (TFs) to this pathway gene recursively with a portion (e.g. 1/10) of least important TFs being excluded in each round of modeling, during which, the importance values of all TFs to the pathway gene were updated and ranked until only one TF was remained in the list. The above procedure, termed BWERF. After that, the importance values of a TF to all pathway genes were aggregated and fitted to a Gaussian mixture model to determine the TF retention for the regulatory layer immediately above the pathway layer. The acquired TFs at the secondary layer were then set to be the new bottom layer to infer the next upper layer, and this process was repeated until a ML-hGRN with the expected layers was obtained. BWERF improved the accuracy for constructing ML-hGRNs because it used backward elimination to exclude the noise genes, and aggregated the individual importance values for determining the TFs retention. We validated the BWERF by using it for constructing ML-hGRNs operating above mouse pluripotency maintenance pathway and Arabidopsis lignocellulosic pathway. Compared to GENIE3, BWERF showed an improvement in recognizing authentic TFs regulating a pathway. Compared to the bottom-up Gaussian graphical model algorithm we developed for constructing ML-hGRNs, the BWERF can construct ML-hGRNs with significantly reduced edges that enable biologists to choose the implicit edges for experimental validation.

Social Cognitive Constructs Did Not Mediate the BEAT Cancer Intervention Effects on Objective Physical Activity Behavior Based on Multivariable Path Analysis.

PubMed

Rogers, Laura Q; Courneya, Kerry S; Anton, Phillip M; Hopkins-Price, Patricia; Verhulst, Steven; Robbs, Randall S; Vicari, Sandra K; McAuley, Edward

2017-04-01

Most breast cancer survivors do not meet physical activity recommendations. Understanding mediators of physical activity behavior change can improve interventions designed to increase physical activity in this at-risk population. Study aims were to determine the 3-month Better Exercise Adherence after Treatment for Cancer (BEAT Cancer) behavior change intervention effects on social cognitive theory constructs and the mediating role of any changes on the increase in accelerometer-measured physical activity previously reported. Post-treatment breast cancer survivors (N = 222) were randomized to BEAT Cancer or usual care. Assessments occurred at baseline, 3 months (M3), and 6 months (M6). Adjusted linear mixed model analysis of variance determined intervention effects on walking self-efficacy, outcome expectations, goal setting, and perceived barrier interference at M3. Path analysis determined mediation of intervention effects on physical activity at M6 by changes in social cognitive constructs during the intervention (i.e., baseline to M3). BEAT Cancer significantly improved self-efficacy, goals, negative outcome expectations, and barriers. Total path analysis model explained 24 % of the variance in M6 physical activity. There were significant paths from randomized intervention group to self-efficacy (β = 0.15, p < .05) and barriers (β = -0.22, p < .01). Barriers demonstrated a borderline significant association with M6 physical activity (β = -0.24, p = .05). No statistically significant indirect effects were found. Although BEAT Cancer significantly improved social cognitive constructs, no significant indirect effects on physical activity improvements 3 months post-intervention were observed (NCT00929617).

Abiotic and Biotic Transformation of TCE under Sulfate Reducing Conditions: the Role of Spatial Heterogeneity (Monterey, CA)

EPA Science Inventory

At a number of sites in the USA, passive reactive barriers built with shredded plant mulch have been constructed to treat ground water contaminated with TCE. These barriers are called biowalls because anaerobic biodegradation of the plant mulch is expected to provide substrates ...

Cycle Commuting and Perceptions of Barriers: Stages of Change, Gender and Occupation

ERIC Educational Resources Information Center

van Bekkum, Jennifer E.; Williams, Joanne M.; Morris, Paul Graham

2011-01-01

Purpose: The aim of this study is to investigate perceptions of cycle commuting barriers in relation to stage of change, gender and occupational role. Stage of change is a key construct of the transtheoretical model of behaviour change that defines behavioural readiness (intentions and actions) into five distinct categories.…

41 CFR 102-76.60 - To which facilities does the Architectural Barriers Act apply?

Code of Federal Regulations, 2012 CFR

2012-01-01

... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false To which facilities does... Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 76-DESIGN AND CONSTRUCTION Architectural Barriers Act § 102-76.60 To which facilities does the...

41 CFR 102-76.60 - To which facilities does the Architectural Barriers Act apply?

Code of Federal Regulations, 2011 CFR

2011-01-01

... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false To which facilities does... Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 76-DESIGN AND CONSTRUCTION Architectural Barriers Act § 102-76.60 To which facilities does the...

41 CFR 102-76.60 - To which facilities does the Architectural Barriers Act apply?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false To which facilities does... Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 76-DESIGN AND CONSTRUCTION Architectural Barriers Act § 102-76.60 To which facilities does the...

41 CFR 102-76.60 - To which facilities does the Architectural Barriers Act apply?

Code of Federal Regulations, 2014 CFR

2014-01-01

... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false To which facilities does... Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 76-DESIGN AND CONSTRUCTION Architectural Barriers Act § 102-76.60 To which facilities does the...

Barriers to Professionalism in the Native-Speaking English Teacher Scheme in Hong Kong

ERIC Educational Resources Information Center

Moorhouse, Benjamin Luke

2017-01-01

This article reports on a small-scale exploratory study that examined how native-speaking English teachers (NETs) working in the Primary Native-speaking English Teacher (PNET) Scheme construct their professional identity(ies) and explored the barriers to their professionalism that exist within their role and context. Data were collected using…

Teacher Behavioral Practices: Relations to Student Risk Behaviors, Learning Barriers, and School Climate

ERIC Educational Resources Information Center

Martinez, Andrew; Mcmahon, Susan D.; Coker, Crystal; Keys, Christopher B.

2016-01-01

Student behavioral problems pose a myriad of challenges for schools. In this study, we examine the relations among teacher and school-level constructs (i.e., teacher collaboration, supervision/discipline, instructional management), and student-related outcomes (i.e., high-risk behaviors, barriers to learning, student social-behavioral climate).…

41 CFR 102-76.60 - To which facilities does the Architectural Barriers Act apply?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false To which facilities does... Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION REAL PROPERTY 76-DESIGN AND CONSTRUCTION Architectural Barriers Act § 102-76.60 To which facilities does the...

Simulations and Games: Use and Barriers in Higher Education

ERIC Educational Resources Information Center

Lean, Jonathan; Moizer, Jonathan; Towler, Michael; Abbey, Caroline

2006-01-01

This article explores the use of simulations and games in tertiary education. It examines the extent to which academics use different simulation-based teaching approaches and how they perceive the barriers to adopting such techniques. Following a review of the extant literature, a typology of simulations is constructed. A staff survey within a UK…

Construction of Barrier in a Fishing Game With Point Capture.

PubMed

Zha, Wenzhong; Chen, Jie; Peng, Zhihong; Gu, Dongbing

2017-06-01

This paper addresses a particular pursuit-evasion game, called as "fishing game" where a faster evader attempts to pass the gap between two pursuers. We are concerned with the conditions under which the evader or pursuers can win the game. This is a game of kind in which an essential aspect, barrier, separates the state space into disjoint parts associated with each player's winning region. We present a method of explicit policy to construct the barrier. This method divides the fishing game into two subgames related to the included angle and the relative distances between the evader and the pursuers, respectively, and then analyzes the possibility of capture or escape for each subgame to ascertain the analytical forms of the barrier. Furthermore, we fuse the games of kind and degree by solving the optimal control strategies in the minimum time for each player when the initial state lies in their winning regions. Along with the optimal strategies, the trajectories of the players are delineated and the upper bounds of their winning times are also derived.

Towards Self-Assembled Hybrid Artificial Cells: Novel Bottom-Up Approaches to Functional Synthetic Membranes

PubMed Central

Brea, Roberto J.; Hardy, Michael D.; Devaraj, Neal K.

2015-01-01

There has been increasing interest in utilizing bottom-up approaches to develop synthetic cells. A popular methodology is the integration of functionalized synthetic membranes with biological systems, producing “hybrid” artificial cells. This Concept article covers recent advances and the current state-of-the-art of such hybrid systems. Specifically, we describe minimal supramolecular constructs that faithfully mimic the structure and/or function of living cells, often by controlling the assembly of highly ordered membrane architectures with defined functionality. These studies give us a deeper understanding of the nature of living systems, bring new insights into the origin of cellular life, and provide novel synthetic chassis for advancing synthetic biology. PMID:26149747

Evaluation of leachate emissions from crushed rock and municipal solid waste incineration bottom ash used in road construction.

PubMed

Lidelöw, S; Lagerkvist, A

2007-01-01

Three years of leachate emissions from municipal solid waste incineration bottom ash and crushed rock in a full-scale test road were evaluated. The impact of time, construction design, and climate on the emissions was studied, and the predicted release from standard leaching tests was compared with the measured release from the road. The main pollutants and their respective concentrations in leachate from the roadside slope were Al (12.8-85.3 mg l(-1)), Cr (2-125 microg l(-1)), and Cu (0.15-1.9 mg l(-1)) in ash leachate and Zn (1-780 microg l(-1)) in crushed rock leachate. From the ash, the initial Cl(-) release was high ( approximately 20 g l(-1)). After three years, the amount of Cu and Cl(-) was in the same range in both leachates, while that of Al and Cr still was more than one order of magnitude higher in ash leachate. Generally, the release was faster from material in the uncovered slopes than below the pavement. Whether the road was asphalted or not, however, had minor impacts on the leachate quality. During rain events, diluted leachates with respect to, e.g., salts were observed. The leaching tests failed to simulate field leaching from the crushed rock, whereas better agreement was observed for the ash. Comparisons of constituent release from bottom ash and conventional materials solely based on such tests should be avoided.

Method and apparatus for constructing an underground barrier wall structure

DOEpatents

Dwyer, Brian P.; Stewart, Willis E.; Dwyer, Stephen F.

2002-01-01

A method and apparatus for constructing a underground barrier wall structure using a jet grout injector subassembly comprising a pair of primary nozzles and a plurality of secondary nozzles, the secondary nozzles having a smaller diameter than the primary nozzles, for injecting grout in directions other than the primary direction, which creates a barrier wall panel having a substantially uniform wall thickess. This invention addresses the problem of the weak "bow-tie" shape that is formed during conventional jet injection when using only a pair of primary nozzles. The improvement is accomplished by using at least four secondary nozzles, of smaller diameter, located on both sides of the primary nozzles. These additional secondary nozzles spray grout or permeable reactive materials in other directions optimized to fill in the thin regions of the bow-tie shape. The result is a panel with increased strength and substantially uniform wall thickness.

A modified gradient approach for the growth of low-density InAs quantum dot molecules by molecular beam epitaxy

NASA Astrophysics Data System (ADS)

Sharma, Nandlal; Reuter, Dirk

2017-11-01

Two vertically stacked quantum dots that are electronically coupled, so called quantum dot molecules, are of great interest for the realization of solid state building blocks for quantum communication networks. We present a modified gradient approach to realize InAs quantum dot molecules with a low areal density so that single quantum dot molecules can be optically addressed. The individual quantum dot layers were prepared by solid source molecular beam epitaxy depositing InAs on GaAs(100). The bottom quantum dot layer has been grown without substrate rotation resulting in an In-gradient across the surface, which translated into a density gradient with low quantum dot density in a certain region of the wafer. For the top quantum dot layer, separated from the bottom quantum dot layer by a 6 nm thick GaAs barrier, various InAs amounts were deposited without an In-gradient. In spite of the absence of an In-gradient, a pronounced density gradient is observed for the top quantum dots. Even for an In-amount slightly below the critical thickness for a single dot layer, a density gradient in the top quantum dot layer, which seems to reproduce the density gradient in the bottom layer, is observed. For more or less In, respectively, deviations from this behavior occur. We suggest that the obvious influence of the bottom quantum dot layer on the growth of the top quantum dots is due to the strain field induced by the buried dots.

Complex carbonate and clastic stratigraphy of the inner shelf off west-central Florida

DOE Office of Scientific and Technical Information (OSTI.GOV)

Locker, S.D.; Doyle, L.J.; Hine, A.C.

1990-05-01

The near surface stratigraphy (< 30 m) of the inner shelf off the west coast of Florida was investigated using high-resolution seismic, side-scan sonar, and continuous underwater video camera coverage. The simultaneous operation of all three systems provided a unique opportunity to calibrate acoustic data with actual video images of the sea floor in a geologically complex area characterized by limestone dissolution structures, hard-bottom exposures, and overlain by a limited supply of terrigenous clastics. Three principle bottom types, grass, sand, and hard-bottom mapped using video and side-scan sonographs, show a correlation with two subsurface stratigraphic zones. The nearshore subsurface zonemore » extending to 6-7 m water depth is characterized by flat or rolling strata and sinkholes that increase in size (200-1,200 m in diameter) and become more numerous further offshore. This zone is truncated by a major erosional unconformity overlain by a thin (<3 m) sequence of Holocene sediment, which together form a terrace upon which the Anclote Key barrier island formed. The offshore subsurface zone (7-11 m water depth) exhibits irregular and discontinuous high-amplitude flat or inclined reflections and few sinkholes. Offshore, extensive hard-bottom exposures are common with discontinuous sediment that occur as lenses or sand waves. The complex stratigraphy of the west Florida shelf includes outcropping Neogene limestones that have undergone dissolution during sea level lowstands. Carbonates and clastics dispersed during multiple sea level changes overlie the Neogene limestones. Dissolution styles and erosional unconformities produced bedrock topography and now control modern geological and biological processes.« less

Effects of beach morphology and waves on onshore larval transport

NASA Astrophysics Data System (ADS)

Fujimura, A.; Reniers, A.; Paris, C. B.; Shanks, A.; MacMahan, J.; Morgan, S.

2015-12-01

Larvae of intertidal species grow offshore, and migrate back to the shore when they are ready to settle on their adult substrates. In order to reach the habitat, they must cross the surf zone, which is characterized as a semi-permeable barrier. This is accomplished through physical forcing (i.e., waves and current) as well as their own behavior. Two possible scenarios of onshore larval transport are proposed: Negatively buoyant larvae stay in the bottom boundary layer because of turbulence-dependent sinking behavior, and are carried toward the shore by streaming of the bottom boundary layer; positively buoyant larvae move to the shore during onshore wind events, and sink to the bottom once they encounter high turbulence (i.e., surf zone edge), where they are carried by the bottom current toward the shore (Fujimura et al. 2014). Our biophysical Lagrangian particle tracking model helps to explain how beach morphology and wave conditions affect larval distribution patterns and abundance. Model results and field observations show that larval abundance in the surf zone is higher at mildly sloped, rip-channeled beaches than at steep pocket beaches. Beach attributes are broken up to examine which and how beach configuration factors affect larval abundance. Modeling with alongshore uniform beaches with variable slopes reveal that larval populations in the surf zone are negatively correlated with beach steepness. Alongshore variability enhances onshore larval transport because of increased cross-shore water exchange by rip currents. Wave groups produce transient rip currents and enhance cross-shore exchange. Effects of other wave components, such as wave height and breaking wave rollers are also considered.

Validating the Modified Drug Adherence Work-Up (M-DRAW) Tool to Identify and Address Barriers to Medication Adherence.

PubMed

Lee, Sun; Bae, Yuna H; Worley, Marcia; Law, Anandi

2017-09-08

Barriers to medication adherence stem from multiple factors. An effective and convenient tool is needed to identify these barriers so that clinicians can provide a tailored, patient-centered consultation with patients. The Modified Drug Adherence Work-up Tool (M-DRAW) was developed as a 13-item checklist questionnaire to identify barriers to medication adherence. The response scale was a 4-point Likert scale of frequency of occurrence (1 = never to 4 = often). The checklist was accompanied by a GUIDE that provided corresponding motivational interview-based intervention strategies for each identified barrier. The current pilot study examined the psychometric properties of the M-DRAW checklist (reliability, responsiveness and discriminant validity) in patients taking one or more prescription medication(s) for chronic conditions. A cross-sectional sample of 26 patients was recruited between December 2015 and March 2016 at an academic medical center pharmacy in Southern California. A priming question that assessed self-reported adherence was used to separate participants into the control group of 17 "adherers" (65.4%), and into the intervention group of nine "unintentional and intentional non-adherers" (34.6%). Comparable baseline characteristics were observed between the two groups. The M-DRAW checklist showed acceptable reliability (13 item; alpha = 0.74) for identifying factors and barriers leading to medication non-adherence. Discriminant validity of the tool and the priming question was established by the four-fold number of barriers to adherence identified within the self-selected intervention group compared to the control group (4.4 versus 1.2 barriers, p < 0.05). The current study did not investigate construct validity due to small sample size and challenges on follow-up with patients. Future testing of the tool will include construct validation.

16 CFR 1034.151 - Program accessibility: New construction and alterations.

Code of Federal Regulations, 2010 CFR

2010-01-01

... alterations. 1034.151 Section 1034.151 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION GENERAL... PRODUCT SAFETY COMMISSION § 1034.151 Program accessibility: New construction and alterations. Each... handicapped persons. The definitions, requirements, and standards of the Architectural Barriers Act (42 U.S.C...

Evaluation of timber barricades and precast concrete traffic barriers for use in highway construction areas.

DOT National Transportation Integrated Search

1976-01-01

On August 15, 1975, the National Transportation Safety Board submitted a number of recommendations to the Administrator of the Federal Highway Administration and the Governor of Virginia regarding safety practices in the construction zone of I-495 in...

A qualitative investigation of Hispanic construction worker perspectives on factors impacting worksite safety and risk

PubMed Central

2011-01-01

Background Hispanic workers have higher rates of injury and death on construction worksites than workers of other ethnicities. Language barriers and cultural differences have been hypothesized as reasons behind the disparate rates. Methods We conducted two series of focus groups with union and non-union Hispanic construction workers to ask them about their perceptions of the causes for the unequal rates. Spanish transcripts were translated and coded in QSR NVivo software for common themes. Results Workers reported a difficult work environment characterized by supervisor pressure, competition for jobs and intimidation with regard to raising safety concerns. Language barriers or cultural factors were not strongly represented as causative factors behind the rates. Conclusion The results of this study have informed the development of an intervention trial that seeks to prevent falls and silica dust exposure by training contractors employing Hispanic construction workers in the elements of safety leadership, including building respect for their Hispanic workers and facilitating their participation in a safety program. PMID:21962128

A physical model describing the interaction of nuclear transport receptors with FG nucleoporin domain assemblies.

PubMed

Zahn, Raphael; Osmanović, Dino; Ehret, Severin; Araya Callis, Carolina; Frey, Steffen; Stewart, Murray; You, Changjiang; Görlich, Dirk; Hoogenboom, Bart W; Richter, Ralf P

2016-04-08

The permeability barrier of nuclear pore complexes (NPCs) controls bulk nucleocytoplasmic exchange. It consists of nucleoporin domains rich in phenylalanine-glycine motifs (FG domains). As a bottom-up nanoscale model for the permeability barrier, we have used planar films produced with three different end-grafted FG domains, and quantitatively analyzed the binding of two different nuclear transport receptors (NTRs), NTF2 and Importin β, together with the concomitant film thickness changes. NTR binding caused only moderate changes in film thickness; the binding isotherms showed negative cooperativity and could all be mapped onto a single master curve. This universal NTR binding behavior - a key element for the transport selectivity of the NPC - was quantitatively reproduced by a physical model that treats FG domains as regular, flexible polymers, and NTRs as spherical colloids with a homogeneous surface, ignoring the detailed arrangement of interaction sites along FG domains and on the NTR surface.

Optically controlled electroresistance and electrically controlled photovoltage in ferroelectric tunnel junctions

PubMed Central

Jin Hu, Wei; Wang, Zhihong; Yu, Weili; Wu, Tom

2016-01-01

Ferroelectric tunnel junctions (FTJs) have recently attracted considerable interest as a promising candidate for applications in the next-generation non-volatile memory technology. In this work, using an ultrathin (3 nm) ferroelectric Sm0.1Bi0.9FeO3 layer as the tunnelling barrier and a semiconducting Nb-doped SrTiO3 single crystal as the bottom electrode, we achieve a tunnelling electroresistance as large as 105. Furthermore, the FTJ memory states could be modulated by light illumination, which is accompanied by a hysteretic photovoltaic effect. These complimentary effects are attributed to the bias- and light-induced modulation of the tunnel barrier, both in height and width, at the semiconductor/ferroelectric interface. Overall, the highly tunable tunnelling electroresistance and the correlated photovoltaic functionalities provide a new route for producing and non-destructively sensing multiple non-volatile electronic states in such FTJs. PMID:26924259

La2/3Sr1/3MnO3-La0.1Bi0.9MnO3 heterostructures for spin filtering

NASA Astrophysics Data System (ADS)

Gajek, M.; Bibes, M.; Varela, M.; Fontcuberta, J.; Herranz, G.; Fusil, S.; Bouzehouane, K.; Barthélémy, A.; Fert, A.

2006-04-01

We have grown heterostructures associating half-metallic La2/3Sr1/3MnO3 (LSMO) bottom electrodes and ferromagnetic La0.1Bi0.9MnO3 (LBMO) tunnel barriers. The layers in the heterostructures have good structural properties and top LBMO films (4 nm thick) have a very low roughness when deposited onto LSMO/SrTiO3(1.6 nm) templates. The LBMO films show an insulating behavior and a ferromagnetic character that are both preserved down to very low thicknesses. They are thus suitable for being used as tunnel barriers. Spin-dependent transport measurements performed on tunnel junctions defined from LSMO/SrTiO3/LBMO/Au samples show a magnetoresistance of up to ~90% at low temperature and bias. This evidences a spin-filtering effect by the LBMO layer, with a spin-filtering efficiency of ~35%.

Irradiation of 4H-SiC UV detectors with heavy ions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kalinina, E. V., E-mail: evk@mail.ioffe.ru; Lebedev, A. A.; Bogdanova, E.

Ultraviolet (UV) photodetectors based on Schottky barriers to 4H-SiC are formed on lightly doped n-type epitaxial layers grown by the chemical vapor deposition method on commercial substrates. The diode structures are irradiated at 25°C by 167-MeV Xe ions with a mass of 131 amu at a fluence of 6 × 10{sup 9} cm{sup −2}. Comparative studies of the optical and electrical properties of as-grown and irradiated structures with Schottky barriers are carried out in the temperature range 23–180°C. The specific features of changes in the photosensitivity and electrical characteristics of the detector structures are accounted for by the capture ofmore » photogenerated carriers into traps formed due to fluctuations of the conduction-band bottom and valence-band top, with subsequent thermal dissociation.« less

Survey datasets on women participation in green jobs in the construction industry.

PubMed

Afolabi, Adedeji O; Ojelabi, Rapheal A; Tunji-Olayeni, Patience F; Fagbenle, Olabosipo I; Mosaku, Timothy O

2018-04-01

The unique qualities of women can make them bearers of solutions towards achieving sustainability and dealing with the dangers attributed to climate change. The attitudinal study utilized a questionnaire instrument to obtain perception of female construction professionals. By using a well-structured questionnaire, data was obtained on women participating in green jobs in the construction Industry. Descriptive statistics is performed on the collected data and presented in tables and mean scores (MS). In addition, inferential statistics of categorical regression was performed on the data to determine the level of influence (beta factor) the identified barriers had on the level of participation in green jobs. Barriers and the socio-economic benefits which can guide policies and actions on attracting, retaining and exploring the capabilities of women in green jobs can be obtained from the survey data when analyzed.

Seafloor Construction Experiment, SEACON II An Instrumented Tri-Moor for Evaluating Undersea Cable Structure Technology

DTIC Science & Technology

1976-12-01

ik’sigi. of undcruater cattle arrays wt’uld opertioal onsraitsbe the primari goali Arr. consitruction technolog% deseclopmcnt %%A% a %ccont!aro goal...weight of 12,500 pounds. struction mooring anchor was pulled out while load The anchor is composed of a 7-foot by 8-foot by and displacement were...out of the bottom. In contrast, anchor AI pulled out to 27,000 pounds for the construction moor anchor. at a load of 3,500 pounds although a 10,000

Credit BG. Interior view of Building 4316, showing internal construction ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Credit BG. Interior view of Building 4316, showing internal construction of water reservoir, roof, and monitor. View looks southeast (142°). The pipe which hangs from the roof structure and turns downward under the monitor supplies water to the reservoir; the plate suspended on chains beneath the pipe end deflects water stream so it does not erode the bottom of the reservoir. The intake pipe for the pumps is not visible in this view - Edwards Air Force Base, North Base, Deluge Water Storage Building, Near Second & D Streets, Boron, Kern County, CA

4. TROJAN MILL, DETAIL OF CRUDE ORE BINS FROM NORTH, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. TROJAN MILL, DETAIL OF CRUDE ORE BINS FROM NORTH, c. 1912. SHOWS TIMBER FRAMING UNDER CONSTRUCTION FOR EAST AND WEST CRUDE ORE BINS AT PREVIOUS LOCATION OF CRUSHER HOUSE, AND SNOW SHED PRESENT OVER SOUTH CRUDE ORE BIN WITH PHASE CHANGE IN SNOW SHED CONSTRUCTION INDICATED AT EAST END OF EAST CRUDE ORE BIN. THIS PHOTOGRAPH IS THE FIRST IMAGE OF THE MACHINE SHOP, UPPER LEFT CORNER. CREDIT JW. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

Seismic Stability Evaluation of Ririe Dam and Reservoir Project. Report 1. Construction History and Field and Laboratory Studies. Volume 1. Main Text

DTIC Science & Technology

1991-09-01

truck Service truck Steel casing, 8-foot diameter with 3/4-inch wall thickness, was installed as the shaft was advanced. A shaft cover, constructed of... steel mats. was hoisted over the shaft at night for security. To obtain in-situ density tests at selected intervals in the bottom of the shaft...subcontractor installed the three wells using an air-rotary rig, and driving steel casing as the wells were advanced. He then perforated the casings

77 FR 32573 - Takes of Marine Mammals Incidental to Specified Activities; Construction and Race Event...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-01

... operations, support space, media operations, hospitality services, sponsored commercial space, and...). Intertidal habitats in the Central Bay, or those that lie between low and high tides, include sandy beaches... sediment and hard substrate habitat. Soft bottom substrate ranges between soft mud with high silt and clay...

Research and Development: A Complex Relationship Part I [and] Part II.

ERIC Educational Resources Information Center

Pollard, John Douglas Edward

Part 1 of this document describes the background, format, and early groundwork that went into the development of a test sponsored entirely by private enterprise. The discipline imposed by a financial bottom line imposes special pressures but also offers new opportunities. This private enterprise model is a multi-constructional process where…

29 CFR 1926.152 - Flammable liquids.

Code of Federal Regulations, 2014 CFR

2014-07-01

... to permit approach of fire control apparatus. (3) The storage area shall be graded in a manner to... feet of each portable tank, there shall be a 12-foot-wide access way to permit approach of fire control... storage cabinets shall be constructed in the following manner, or equivalent: The bottom, sides, and top...

MICROBIAL SOLUTION: APPLICATION OF MICROORGANISMS FOR BIOFUEL PRODUCTION AND CO2 MITIGATION

EPA Science Inventory

A 100 L photobioreactor for biodiesel generation from microalga Chlorella vulgaris was constructed from two parallel clear PVC 10 feet tubes (6’ diameter) with a small slope (10%). The gas mixture (5% CO2 and air) flowed up the top of the PVC tubes from the bottom as...

Heat pump water heater and method of making the same

DOEpatents

Mei, Viung C.; Tomlinson, John J.; Chen, Fang C.

2001-01-01

An improved heat pump water heater wherein the condenser assembly of the heat pump is inserted into the water tank through an existing opening in the top of the tank, the assembly comprising a tube-in-a-tube construction with an elongated cylindrical outer body heat exchanger having a closed bottom with the superheated refrigerant that exits the compressor of the heat pump entering the top of the outer body. As the refrigerant condenses along the interior surface of the outer body, the heat from the refrigerant is transferred to the water through the outer body. The refrigerant then enters the bottom of an inner body coaxially disposed within the outer body and exits the top of the inner body into the refrigerant conduit leading into the expansion device of the heat pump. The outer body, in a second embodiment of the invention, acts not only as a heat exchanger but also as the sacrificial anode in the water tank by being constructed of a metal which is more likely to corrode than the metal of the tank.

'Top, bottom, versatile': narratives of sexual practices in gay relationships in the Cape Metropole, South Africa.

PubMed

Henderson, Neil John

2017-07-13

Sexual practices among gay and other men who have sex with men are evolving in South Africa and heteronormative stereotypes are being contested. This paper draws from a larger qualitative study on how men construct a gay identity and negotiate their relationships within contemporary South African contexts, following constitutional and legal changes, in this respect. A feminist, social constructionist approach was used to collect and analyse data from in-depth interviews with 15 self-identified gay men, aged 20 to 46 years, drawn from a university in the larger Cape Metropole, South Africa. Interviews were audio-recorded, transcribed verbatim and analysed using thematic and narrative analysis. 'Bottoms' revealed being powerful in receptive sex. Other men deconstructed the binaries of masculine/feminine and resisted heteronormativity by engaging in fluid constructions in their relationships, whereby participants 'switched' or 'flipped' or did not recognise stereotypical roles when practising sex. There may be value in making these flexible and reciprocal sexual practices better known about and promoted as non-normative African models of sexual practice.

Bottom-up construction of artificial molecules for superconducting quantum processors

NASA Astrophysics Data System (ADS)

Poletto, Stefano; Rigetti, Chad; Gambetta, Jay M.; Merkel, Seth; Chow, Jerry M.; Corcoles, Antonio D.; Smolin, John A.; Rozen, Jim R.; Keefe, George A.; Rothwell, Mary B.; Ketchen, Mark B.; Steffen, Matthias

2012-02-01

Recent experiments on transmon qubits capacitively coupled to superconducting 3-dimensional cavities have shown coherence times much longer than transmons coupled to more traditional planar resonators. For the implementation of a quantum processor this approach has clear advantages over traditional techniques but it poses the challenge of scalability. We are currently implementing multi-qubits experiments based on a bottom-up scaling approach. First, transmon qubits are fabricated on individual chips and are independently characterized. Second, an artificial molecule is assembled by selecting a particular set of previously characterized single-transmon chips. We present recent data on a two-qubit artificial molecule constructed in this way. The two qubits are chosen to generate a strong Z-Z interaction by matching the 0-1 transition energy of one qubit with the 1-2 transition of the other. Single qubit manipulations and state tomography cannot be done with ``traditional'' single tone microwave pulses but instead specifically shaped pulses have to be simultaneously applied on both qubits. Coherence times, coupling strength, and optimal pulses for decoupling the two qubits and perform state tomography are presented

Underground barrier construction apparatus with soil-retaining shield

DOEpatents

Gardner, B.M.; Smith, A.M.; Hanson, R.W.; Hodges, R.T.

1998-08-04

An apparatus is described for building a horizontal underground barrier by cutting through soil and depositing a slurry, preferably one which cures into a hardened material. The apparatus includes a digging means for cutting and removing soil to create a void under the surface of the ground, a shield means for maintaining the void, and injection means for inserting barrier-forming material into the void. In one embodiment, the digging means is a continuous cutting chain. Mounted on the continuous cutting chain are cutter teeth for cutting through soil and discharge paddles for removing the loosened soil. This invention includes a barrier placement machine, a method for building an underground horizontal containment barrier using the barrier placement machine, and the underground containment system. Preferably the underground containment barrier goes underneath and around the site to be contained in a bathtub-type containment. 17 figs.

Treatment barriers identified by substance abusers assessed at a centralized intake unit.

PubMed

Rapp, Richard C; Xu, Jiangmin; Carr, Carey A; Lane, D Tim; Wang, Jichuan; Carlson, Robert

2006-04-01

The 59-item Barriers to Treatment Inventory (BTI) was administered to 312 substance abusers at a centralized intake unit following assessment but before treatment entry to assess their views on barriers to treatment. Factor analysis identified 25 items in 7 well-defined latent constructs: Absence of Problem, Negative Social Support, Fear of Treatment, Privacy Concerns, Time Conflict, Poor Treatment Availability, and Admission Difficulty. The factorial structure of the barriers is consistent with the findings of other studies that asked substance abusers about barriers to treatment and is conceptually compatible with Andersen's model of health care utilization. Factors were moderately to highly correlated, suggesting that they interact with one another. Selected characteristics were generally not predictive of barrier factors. Overall, results indicate that the BTI has good content validity and is a reliable instrument for assessing barriers to drug treatment. The potential utility of the BTI in assessment settings is discussed.

Self-organized nickel nanoparticles on nanostructured silicon substrate intermediated by a titanium oxynitride (TiNxOy) interface

NASA Astrophysics Data System (ADS)

Morales, M.; Droppa, R., Jr.; de Mello, S. R. S.; Figueroa, C. A.; Zanatta, A. R.; Alvarez, F.

2018-01-01

In this work we report an experimental approach by combining in situ sequential top-down and bottom-up processes to induce the organization of nanosized nickel particles. The top-down process consists in xenon ion bombardment of a crystalline silicon substrate to generate a pattern, followed by depositing a ˜15 nm titanium oxynitride thin film to act as a metallic diffusion barrier. Then, metallic nanoparticles are deposited by argon ion sputtering a pure nickel target, and the sample is annealed to promote the organization of the nickel nanoparticles (a bottom-up process). According to the experimental results, the surface pattern and the substrate biaxial surface strain are the driving forces behind the alignment and organization of the nickel nanoparticles. Moreover, the ratio between the F of metallic atoms arriving at the substrate relative to its surface diffusion mobility determines the nucleation regime of the nickel nanoparticles. These features are presented and discussed considering the existing technical literature on the subject.

Photographic copy of photograph, aerial view looking north and showing ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photographic copy of photograph, aerial view looking north and showing Test Stand 'A' (at bottom), Test Stand 'B' (upper right), and a portion of Test Stand 'C' (top of view). Compare HAER CA-163-1 and 2 and note addition of liquid nitrogen storage tank (Building 4262/E-63) to west of Test Stand 'C' as well as various ancillary facilities located behind earth barriers near Test Stand 'C.' (JPL negative no. 384-3006-A, 12 December 1961) - Jet Propulsion Laboratory Edwards Facility, Edwards Air Force Base, Boron, Kern County, CA

Design of a Bottom Impermeable Barrier in Conjunction with A contaminated Site Containment Structure.

DTIC Science & Technology

1994-05-01

utilizes drill bits and tubing to cut through the soil. Unlike the auger method, a slurry mixture is used to keep the drill bit clean and assist in...is applied. In the sleeve pipe method, or also called tube -a-manchette, the sleeve pipe is installed in the grout hole, and sealed in place with a...acts as a one-way valve. allowing grout out of the pipe, but not back into the sleeve. A grouting tube with double packer is used to inject the grout

Rational F-theory GUTs without exotics

NASA Astrophysics Data System (ADS)

Krippendorf, Sven; Peña, Damián Kaloni Mayorga; Oehlmann, Paul-Konstantin; Ruehle, Fabian

2014-07-01

We construct F-theory GUT models without exotic matter, leading to the MSSM matter spectrum with potential singlet extensions. The interplay of engineering explicit geometric setups, absence of four-dimensional anomalies, and realistic phenomenology of the couplings places severe constraints on the allowed local models in a given geometry. In constructions based on the spectral cover we find no model satisfying all these requirements. We then provide a survey of models with additional U(1) symmetries arising from rational sections of the elliptic fibration in toric constructions and obtain phenomenologically appealing models based on SU(5) tops. Furthermore we perform a bottom-up exploration beyond the toric section constructions discussed in the literature so far and identify benchmark models passing all our criteria, which can serve as a guideline for future geometric engineering.

Psychometrics of a new questionnaire to assess glaucoma adherence: the Glaucoma Treatment Compliance Assessment Tool (an American Ophthalmological Society thesis).

PubMed

Mansberger, Steven L; Sheppler, Christina R; McClure, Tina M; Vanalstine, Cory L; Swanson, Ingrid L; Stoumbos, Zoey; Lambert, William E

2013-09-01

To report the psychometrics of the Glaucoma Treatment Compliance Assessment Tool (GTCAT), a new questionnaire designed to assess adherence with glaucoma therapy. We developed the questionnaire according to the constructs of the Health Belief Model. We evaluated the questionnaire using data from a cross-sectional study with focus groups (n = 20) and a prospective observational case series (n=58). Principal components analysis provided assessment of construct validity. We repeated the questionnaire after 3 months for test-retest reliability. We evaluated predictive validity using an electronic dosing monitor as an objective measure of adherence. Focus group participants provided 931 statements related to adherence, of which 88.7% (826/931) could be categorized into the constructs of the Health Belief Model. Perceived barriers accounted for 31% (288/931) of statements, cues-to-action 14% (131/931), susceptibility 12% (116/931), benefits 12% (115/931), severity 10% (91/931), and self-efficacy 9% (85/931). The principal components analysis explained 77% of the variance with five components representing Health Belief Model constructs. Reliability analyses showed acceptable Cronbach's alphas (>.70) for four of the seven components (severity, susceptibility, barriers [eye drop administration], and barriers [discomfort]). Predictive validity was high, with several Health Belief Model questions significantly associated (P <.05) with adherence and a correlation coefficient (R (2)) of .40. Test-retest reliability was 90%. The GTCAT shows excellent repeatability, content, construct, and predictive validity for glaucoma adherence. A multisite trial is needed to determine whether the results can be generalized and whether the questionnaire accurately measures the effect of interventions to increase adherence.

Method Producing an SNS Superconducting Junction with Weak Link Barrier

NASA Technical Reports Server (NTRS)

Hunt, Brian D. (Inventor)

1999-01-01

A method of producing a high temperature superconductor Josephson element and an improved SNS weak link barrier element is provided. A YBaCuO superconducting electrode film is deposited on a substrate at a temperature of approximately 800 C. A weak link barrier layer of a nonsuperconducting film of N-YBaCuO is deposited over the electrode at a temperature range of 520 C. to 540 C. at a lower deposition rate. Subsequently a superconducting counter-electrode film layer of YBaCuO is deposited over the weak link barrier layer at approximately 800 C. The weak link barrier layer has a thickness of approximately 50 A and the SNS element can be constructed to provide an edge geometry junction.

Students' Perceptions of Edmodo and Mobile Learning and Their Real Barriers towards Them

ERIC Educational Resources Information Center

Al-Said, Khaleel M.

2015-01-01

The present research aims to investigate the students' perceptions levels of Edmodo and Mobile learning and to identify the real barriers of them at Taibah University in KSA. After implemented Edmodo application as an Mlearning platform, two scales were applied on the research sample, the first scale consisted of 36 statements was constructed to…

Serb guardrail in-service evaluation : S. Ashland to California State Line, F.A.P. IR-5-1(113)00, Jackson County : experimental features construction-report.

DOT National Transportation Integrated Search

1990-03-01

This report covers the installation of two Self-Restoring Barrier (SERB) guardrails on Interstate-5 south of Ashland Oregon. The SERB design was developed to reduce repair cost and increase safety when compared to conventional barriers. This is accom...

A Barrier-Free Home: Considerations and Recommendations for Design. Information Support Packet #3.

ERIC Educational Resources Information Center

Stevens, John H.

This guide is intended to assist people with physical disabilities who are wheelchair users and their families in the construction of a barrier-free home. Introductory information notes the importance of specific planning for individual needs and full participation by the homeowner as well as the architect and contractor. Briefly addressed are:…

On the ASR and ASR thermal residues characterization of full scale treatment plant.

PubMed

Mancini, G; Viotti, P; Luciano, A; Fino, D

2014-02-01

In order to obtain 85% recycling, several procedures on Automotive Shredder Residue (ASR) could be implemented, such as advanced metal and polymer recovery, mechanical recycling, pyrolysis, the direct use of ASR in the cement industry, and/or the direct use of ASR as a secondary raw material. However, many of these recovery options appear to be limited, due to the possible low acceptability of ASR based products on the market. The recovery of bottom ash and slag after an ASR thermal treatment is an option that is not usually considered in most countries (e.g. Italy) due to the excessive amount of contaminants, especially metals. The purpose of this paper is to provide information on the characteristics of ASR and its full-scale incineration residues. Experiments have been carried out, in two different experimental campaigns, in a full-scale tyre incineration plant specifically modified to treat ASR waste. Detailed analysis of ASR samples and combustion residues were carried out and compared with literature data. On the basis of the analytical results, the slag and bottom ash from the combustion process have been classified as non-hazardous wastes, according to the EU waste acceptance criteria (WAC), and therefore after further tests could be used in future in the construction industry. It has also been concluded that ASR bottom ash (EWC - European Waste Catalogue - code 19 01 12) could be landfilled in SNRHW (stabilized non-reactive hazardous waste) cells or used as raw material for road construction, with or without further treatment for the removal of heavy metals. In the case of fly ash from boiler or Air Pollution Control (APC) residues, it has been found that the Cd, Pb and Zn concentrations exceeded regulatory leaching test limits therefore their removal, or a stabilization process, would be essential prior to landfilling the use of these residues as construction material. Copyright © 2013 Elsevier Ltd. All rights reserved.

Multi-layer waste containment barrier

DOEpatents

Smith, Ann Marie; Gardner, Bradley M.; Nickelson, David F.

1999-01-01

An apparatus for constructing an underground containment barrier for containing an in-situ portion of earth. The apparatus includes an excavating device for simultaneously (i) excavating earthen material from beside the in-situ portion of earth without removing the in-situ portion and thereby forming an open side trench defined by opposing earthen sidewalls, and (ii) excavating earthen material from beneath the in-situ portion of earth without removing the in-situ portion and thereby forming a generally horizontal underground trench beneath the in-situ portion defined by opposing earthen sidewalls. The apparatus further includes a barrier-forming device attached to the excavating device for simultaneously forming a side barrier within the open trench and a generally horizontal, multi-layer barrier within the generally horizontal trench. The multi-layer barrier includes at least a first layer and a second layer.

Compact cladding-pumped planar waveguide amplifier and fabrication method

DOEpatents

Bayramian, Andy J.; Beach, Raymond J.; Honea, Eric; Murray, James E.; Payne, Stephen A.

2003-10-28

A low-cost, high performance cladding-pumped planar waveguide amplifier and fabrication method, for deployment in metro and access networks. The waveguide amplifier has a compact monolithic slab architecture preferably formed by first sandwich bonding an erbium-doped core glass slab between two cladding glass slabs to form a multi-layer planar construction, and then slicing the construction into multiple unit constructions. Using lithographic techniques, a silver stripe is deposited and formed at a top or bottom surface of each unit construction and over a cross section of the bonds. By heating the unit construction in an oven and applying an electric field, the silver stripe is then ion diffused to increase the refractive indices of the core and cladding regions, with the diffusion region of the core forming a single mode waveguide, and the silver diffusion cladding region forming a second larger waveguide amenable to cladding pumping with broad area diodes.

Who needs collaborative care treatment? A qualitative study exploring attitudes towards and experiences with mental healthcare among general practitioners and care managers.

PubMed

Møller, Marlene Christina Rosengaard; Mygind, Anna; Bro, Flemming

2018-05-30

Collaborative care treatment is widely recognized as an effective approach to improve the quality of mental healthcare through enhanced and structured collaboration between general practice and specialized psychiatry. However, studies indicate that the complexity of collaborative care treatment interventions challenge the implementation in real-life general practice settings. Four Danish Collaborative Care Models were launched in 2014 for patients with mild/moderate anxiety and depression. These involved collaboration between general practitioners, care managers and consultant psychiatrists. Taking a multi-practice bottom-up approach, this paper aims to explore the perceived barriers and enablers related to collaborative care for patients with mental health problems and to investigate the actual experiences with a Danish collaborative care model in a single-case study in order to identify enablers and barriers for successful implementation. Combining interviews and observations of usual treatment practices, we conducted a multi-practice study among general practitioners who were not involved in the Danish collaborative care models to explore their perspectives on existing mental health treatment and to investigate (from a bottom-up approach) their perceptions of and need for collaborative care in mental health treatment. Additionally, by combining observations and qualitative interviews, we followed the implementation of a Danish collaborative care model in a single-case study to convey identified barriers and enablers of the collaborative care model. Experienced and perceived enablers of the Danish collaborative care model mainly consisted of a need for new treatment options to deal with mild/moderate anxiety and depression. The model was considered to meet the need for a free fast track to high-quality treatment. Experienced barriers included: poor adaptation of the model to the working conditions and needs in daily general practice, time consumption, unsustainable logistical set-up and unclear care manager role. General practitioners in the multi-practice study considered access to treatment and not collaboration with specialised psychiatry to be essential for this group of patients. The study calls for increased attention to implementation processes and better adaptation of collaborative care models to the clinical reality of general practice. Future interventions should address the treatment needs of specific patient populations and should involve relevant stakeholders in the design and implementation processes.

Encapsulation of organic light emitting diodes

NASA Astrophysics Data System (ADS)

Visweswaran, Bhadri

Organic Light Emitting Diodes (OLEDs) are extremely attractive candidates for flexible display and lighting panels due to their high contrast ratio, light weight and flexible nature. However, the materials in an OLED get oxidized by extremely small quantities of atmospheric moisture and oxygen. To obtain a flexible OLED device, a flexible thin-film barrier encapsulation with low permeability for water is necessary. Water permeates through a thin-film barrier by 4 modes: microcracks, contaminant particles, along interfaces, and through the bulk of the material. We have developed a flexible barrier film made by Plasma Enhanced Chemical Vapor Deposition (PECVD) that is devoid of any microcracks. In this work we have systematically reduced the permeation from the other three modes to come up with a barrier film design for an operating lifetime of over 10 years. To provide quantitative feedback during barrier material development, techniques for measuring low diffusion coefficient and solubility of water in a barrier material have been developed. The mechanism of water diffusion in the barrier has been identified. From the measurements, we have created a model for predicting the operating lifetime from accelerated tests when the lifetime is limited by bulk diffusion. To prevent the particle induced water permeation, we have encapsulated artificial particles and have studied their cross section. A three layer thin-film that can coat a particle at thicknesses smaller than the particle diameter is identified. It is demonstrated to protect a bottom emission OLED device that was contaminated with standard sized glass beads. The photoresist and the organic layers below the barrier film causes sideways permeation that can reduce the lifetime set by permeation through the bulk of the barrier. To prevent the sideways permeation, an impermeable inorganic grid made of the same barrier material is designed. The reduction in sideways permeation due to the impermeable inorganic grid is demonstrated in an encapsulated OLED. In this work, we have dealt with three permeation mechanisms and shown solution to each of them. These steps give us reliable flexible encapsulation that has a lifetime of greater than 10 years.

Subtidal eelgrass/macroalgae surveys for the proposed breakwaters at the US Coast Guard Station at Ediz Hook, Washington, March 1993

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shreffler, D.K.

1993-05-01

In 1993, the US Coast Guard proposed to construct two breakwaters and a debris boom to protect its existing pier and moored vessels inside Ediz Hook in Port Angeles Harbor, Washington. To assist the US Army Corps of Engineers -- Seattle District in determining the potential environmental impacts of the proposed breakwaters, Battelle/Marine Sciences Laboratory performed subtidal SCUBA surveys as specified in the Washington Department of Fisheries intermediate eelgrass/macroalgae habitat survey guidelines. The objectives of the subtidal surveys were to (1) quantify the shoot densities of eelgrass; (2) provide percent cover estimates for non-eelgrass macroalgae species; (3) develop a sitemore » map indicating the qualitative distribution of eelgrass/macroalgae species, substrate characterization, approximate depth contours, and the approximate location of the proposed project features; and (4) document the time and date of the surveys, turbidity/visibility, presence of invertebrate/vertebrate species, and anecdotal observations pertinent to habitat characterization of the project site. A total of 14 dives along 12 transects (T1--T12) were successfully completed between March 15 and March 17, 1993. Eelgrass was observed on all of the transects except T7 and T8 at the western debris barrier and T12 along the waterward margin of the existing T-pier. The vicinity of the proposed east breakwater had the highest eelgrass shoot densities (up to 89 shoots/m{sup 2}) observed by the divers. Macroalgae and invertebrate species diversity were also highest at the east breakwater site. The low eelgrass densities observed at the west debris barrier site (0 to 14 shoots/m{sup 2}) can be attributed mostly to the lack of suitable substrate. The existing layer of wood debris armoring the bottom at the west project site currently limits, and in the areas of heaviest deposition probably precludes, the growth of eelgrass. As was expected, no eelgrass was observed at the south breakwater site.« less

CONSTRUCTION, MONITORING, AND PERFORMANCE OF TWO SOIL LINERS

EPA Science Inventory

A prototype soil liner and a field-scale soil liner were constructed to test whether compacted soil barrier systems could be built to meet the standard set by the U.S. Environmental Protection Agency (EPA) for saturated hydraulic conductivity (< 1 x 10'7 cm/s). In situ ponded inf...

Saccade Generation by the Frontal Eye Fields in Rhesus Monkeys Is Separable from Visual Detection and Bottom-Up Attention Shift

PubMed Central

Lee, Kyoung-Min; Ahn, Kyung-Ha; Keller, Edward L.

2012-01-01

The frontal eye fields (FEF), originally identified as an oculomotor cortex, have also been implicated in perceptual functions, such as constructing a visual saliency map and shifting visual attention. Further dissecting the area’s role in the transformation from visual input to oculomotor command has been difficult because of spatial confounding between stimuli and responses and consequently between intermediate cognitive processes, such as attention shift and saccade preparation. Here we developed two tasks in which the visual stimulus and the saccade response were dissociated in space (the extended memory-guided saccade task), and bottom-up attention shift and saccade target selection were independent (the four-alternative delayed saccade task). Reversible inactivation of the FEF in rhesus monkeys disrupted, as expected, contralateral memory-guided saccades, but visual detection was demonstrated to be intact at the same field. Moreover, saccade behavior was impaired when a bottom-up shift of attention was not a prerequisite for saccade target selection, indicating that the inactivation effect was independent of the previously reported dysfunctions in bottom-up attention control. These findings underscore the motor aspect of the area’s functions, especially in situations where saccades are generated by internal cognitive processes, including visual short-term memory and long-term associative memory. PMID:22761923

Saccade generation by the frontal eye fields in rhesus monkeys is separable from visual detection and bottom-up attention shift.

PubMed

Lee, Kyoung-Min; Ahn, Kyung-Ha; Keller, Edward L

2012-01-01

The frontal eye fields (FEF), originally identified as an oculomotor cortex, have also been implicated in perceptual functions, such as constructing a visual saliency map and shifting visual attention. Further dissecting the area's role in the transformation from visual input to oculomotor command has been difficult because of spatial confounding between stimuli and responses and consequently between intermediate cognitive processes, such as attention shift and saccade preparation. Here we developed two tasks in which the visual stimulus and the saccade response were dissociated in space (the extended memory-guided saccade task), and bottom-up attention shift and saccade target selection were independent (the four-alternative delayed saccade task). Reversible inactivation of the FEF in rhesus monkeys disrupted, as expected, contralateral memory-guided saccades, but visual detection was demonstrated to be intact at the same field. Moreover, saccade behavior was impaired when a bottom-up shift of attention was not a prerequisite for saccade target selection, indicating that the inactivation effect was independent of the previously reported dysfunctions in bottom-up attention control. These findings underscore the motor aspect of the area's functions, especially in situations where saccades are generated by internal cognitive processes, including visual short-term memory and long-term associative memory.

Safety Challenges and Improvement Strategies of Ethnic Minority Construction Workers: A Case Study in Hong Kong.

PubMed

Wu, Chunlin; Luo, Xiaowei; Wang, Tao; Wang, Yue; Sapkota, Bibek

2018-04-18

Due to cultural differences, ethnic minority construction workers are more difficult to manage and more vulnerable to accidents. This study aims to identify the major barriers faced by ethnic minority workers from their own perspectives and determine potential strategies to enhance safety climate of construction projects, thus ultimately improve their safety performance. A survey with modified Nordic safety climate questionnaire was conducted in a certain sub-contractor in Hong Kong. In-depth interviews, status quo description, major challenge investigation and safety knowledge tests were carried as well. The top three most important safety challenges identified are improper stereotypes from the whole industry, lack of opportunities for job assignment, and language barriers. To improve the safety performance, employers should allocate sufficient personal protective equipment and governments should organize unannounced site visits more frequently. Besides, the higher-level management should avoid giving contradictory instructions to foremen against to the standards of supervisors.

Characterization of the insulator barrier and the superconducting transition temperature in GdBa{sub 2}Cu{sub 3}O{sub 7−δ}/BaTiO{sub 3} bilayers for application in tunnel junctions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Navarro, H., E-mail: henrynavarro@cab.cnea.gov.ar; Sirena, M.; Haberkorn, N.

2015-07-28

The optimization of the superconducting properties in a bottom electrode and the quality of an insulator barrier are the first steps in the development of superconductor/insulator/superconductor tunnel junctions. Here, we study the quality of a BaTiO{sub 3} tunnel barrier deposited on a 16 nm thick GdBa{sub 2}Cu{sub 3}O{sub 7−δ} thin film by using conductive atomic force microscopy. We find that the tunnel current is systematically reduced (for equal applied voltage) by increasing the BaTiO{sub 3} barrier thickness between 1.6 and 4 nm. The BaTiO{sub 3} layers present an energy barrier of ≈1.2 eV and an attenuation length of 0.35–0.5 nm (depending on the appliedmore » voltage). The GdBa{sub 2}Cu{sub 3}O{sub 7−δ} electrode is totally covered by a BaTiO{sub 3} thickness above 3 nm. The presence of ferroelectricity was verified by piezoresponse force microscopy for a 4 nm thick BaTiO{sub 3} top layer. The superconducting transition temperature of the bilayers is systematically suppressed by increasing the BaTiO{sub 3} thickness. This fact can be associated with stress at the interface and a reduction of the orthorhombicity of the GdBa{sub 2}Cu{sub 3}O{sub 7−δ}. The reduction in the orthorhombicity is expected by considering the interface mismatch and it can also be affected by reduced oxygen stoichiometry (poor oxygen diffusion across the BaTiO{sub 3} barrier)« less

Health Sensing Functions in Thermal Barrier Coatings Incorporating Rare-Earth-Doped Luminescent Sublayers

NASA Technical Reports Server (NTRS)

Eldridge, J. I.; Singh, J.; Wolfe, D. E.

2004-01-01

Great effort has been directed towards developing techniques to monitor the health of thermal barrier coatings (TBCs) that would detect the approach of safety-threatening conditions. An unconventional approach is presented here where health sensing functionality is integrated into the TBC itself by the incorporation of rare-earth-doped luminescent sublayers to monitor erosion as well as whether the TBC is maintaining the underlying substrate at a sufficiently low temperature. Erosion indication is demonstrated in electron-beam physical vapor deposited (EB-PVD) TBCs consisting of 7wt% yttria-stabilized zirconia (7YSZ) with europium-doped and terbium-doped sublayers. Multiple ingot deposition produced sharp boundaries between the doped sublayers without interrupting the columnar growth of the TBC. The TBC-coated specimens were subjected to alumina particle jet erosion, and the erosion depth was then indicated under ultraviolet illumination that excited easily visible luminescence characteristic of sublayer that was exposed by erosion. In addition, temperature measurements from a bottom-lying europium-doped sublayer in a TBC produced by multiple ingot EB-PVD were accomplished by measuring the temperature-dependent decay time from the 606 nm wavelength emission excited in that sublayer with a 532 nm wavelength laser that was selected for its close match to one of the europium excitation wavelengths as well as being at a wavelength where the TBC is relatively transparent. It is proposed the low dopant levels and absence of interruption of the TBC columnar growth allow the addition of the erosion and temperature sensing functions with minimal effects on TBC performance.

Perceived Advantages of 3D Lessons in Constructive Learning for South African Student Teachers Encountering Learning Barriers

ERIC Educational Resources Information Center

de Jager, Thelma

2017-01-01

Research shows that three-dimensional (3D)-animated lessons can contribute to student teachers' effective learning and comprehension, regardless of the learning barriers they experience. Student teachers majoring in the subject Life Sciences in General Subject Didactics viewed 3D images of the heart during lectures. The 3D images employed in the…

Safety Barrier Guidelines for Home Pools [and] How To Plan for the Unexpected.

ERIC Educational Resources Information Center

Consumer Product Safety Commission, Washington, DC.

Each year, hundreds of young children die and thousands come close to death due to submersion in residential swimming pools. The United States Consumer Products Safety Commission studied data on drownings and child behavior, as well as information on pool and pool barrier construction, and concluded that the best way to reduce child drownings in…

Anomalous electron collimation in HgTe quantum wells with inverted band structure.

PubMed

Zou, Y L; Zhang, L B; Song, J T

2013-02-20

We investigate the electron collimation behavior in HgTe quantum wells (QWs) with a magnetic-electric barrier induced by a ferromagnetic metal stripe. We find that electrons can transmit perfectly through the magnetic-electric barrier at some specific incidence angles. These angles can be controlled by the tuning gate voltage, local magnetic field and Fermi energy of incident electrons in QWs with appropriate barrier length. This collimation feature can be used to construct momentum filters in HgTe QWs and has potential application in nanodevices.

Condensation on superhydrophobic surfaces: the role of local energy barriers and structure length scale.

PubMed

Enright, Ryan; Miljkovic, Nenad; Al-Obeidi, Ahmed; Thompson, Carl V; Wang, Evelyn N

2012-10-09

Water condensation on surfaces is a ubiquitous phase-change process that plays a crucial role in nature and across a range of industrial applications, including energy production, desalination, and environmental control. Nanotechnology has created opportunities to manipulate this process through the precise control of surface structure and chemistry, thus enabling the biomimicry of natural surfaces, such as the leaves of certain plant species, to realize superhydrophobic condensation. However, this "bottom-up" wetting process is inadequately described using typical global thermodynamic analyses and remains poorly understood. In this work, we elucidate, through imaging experiments on surfaces with structure length scales ranging from 100 nm to 10 μm and wetting physics, how local energy barriers are essential to understand non-equilibrium condensed droplet morphologies and demonstrate that overcoming these barriers via nucleation-mediated droplet-droplet interactions leads to the emergence of wetting states not predicted by scale-invariant global thermodynamic analysis. This mechanistic understanding offers insight into the role of surface-structure length scale, provides a quantitative basis for designing surfaces optimized for condensation in engineered systems, and promises insight into ice formation on surfaces that initiates with the condensation of subcooled water.

Rectifying behavior in the GaN/graded-AlxGa1‑xN/GaN double heterojunction structure

NASA Astrophysics Data System (ADS)

Wang, Caiwei; Jiang, Yang; Ma, Ziguang; Zuo, Peng; Yan, Shen; Die, Junhui; Wang, Lu; Jia, Haiqiang; Wang, Wenxin; Chen, Hong

2018-05-01

Rectifying characteristics induced by the polarization fields are achieved in the GaN/graded-AlxGa1‑xN/GaN double heterojunction structure (DHS). By grading AlxGa1‑xN from x  =  0.4(0.3) to 0.1, the DHS displays a better conductivity for smaller reverse bias than for forward bias voltages (reverse rectifying behavior) which is opposite to p–n junction rectifying characteristics. The mechanism of reverse rectifying behavior is illustrated via calculating the energy band structures of the samples. The band gap narrowing caused by decreasing Al composition could compensate the for the band tilt due to the polarization effect in AlxGa1‑xN barriers, thus lowering the barrier height for electron transport from top to bottom. The reverse rectifying behavior could be enhanced by increasing the Al content and the thickness of the multi-layer graded AlxGa1‑xN barriers. This work gives a better understanding of the mechanism of carrier transport in a DHS and makes it possible to realize novel GaN-based heterojunction transistors.

Evaluation of Electrical Characteristics and Trap-State Density in Bottom-Gate Polycrystalline Thin Film Transistors Processed with High-Pressure Water Vapor Annealing

NASA Astrophysics Data System (ADS)

Kunii, Masafumi

2006-02-01

This paper discusses electrical characteristics and trap-state density in polycrystalline silicon (poly-Si) used in bottom-gate poly-Si thin film transistors (TFTs) processed with high-pressure water vapor annealing (HWA). The threshold voltage uniformity of the HWA-processed TFTs is improved by 42% for N-channel and 38% for P-channel TFTs in terms of standard deviation, and carrier mobility is enhanced by 10% or greater for both N- and P-channel TFTs than those TFTs processed conventionally. Subthreshold swing is also improved by HWA, showing that HWA postannealing is effective for improving the Si/SiO2 interface of the bottom-gate TFTs. Two types of TFTs having different poly-Si crystallinities are examined to investigate carrier transport in poly-Si processed by HWA postannealing. The evaluation of trap-state density for the two types of poly-Si reveals that HWA postannealing is more efficient for N-channel than for P-channel TFTs. Furthermore, HWA postannealing is more effective for poly-Si with high crystallinity to improve TFT characteristics. The analysis of the trap-state distributions and the activation energy of TFT drain current indicate that HWA deactivates dangling bonds highly localized at poly-Si grain boundaries (GBs). Thus, HWA postannealing effects can be interpreted by a GB barrier potential model similar to that applied to conventional hydrogenation.

[Correlation of substrate structure and hydraulic characteristics in subsurface flow constructed wetlands].

PubMed

Bai, Shao-Yuan; Song, Zhi-Xin; Ding, Yan-Li; You, Shao-Hong; He, Shan

2014-02-01

The correlation of substrate structure and hydraulic characteristics was studied by numerical simulation combined with experimental method. The numerical simulation results showed that the permeability coefficient of matrix had a great influence on hydraulic efficiency in subsurface flow constructed wetlands. The filler with a high permeability coefficient had a worse flow field distribution in the constructed wetland with single layer structure. The layered substrate structure with the filler permeability coefficient increased from surface to bottom could avoid the short-circuited flow and dead-zones, and thus, increased the hydraulic efficiency. Two parallel pilot-scale constructed wetlands were built according to the numerical simulation results, and tracer experiments were conducted to validate the simulation results. The tracer experiment result showed that hydraulic characteristics in the layered constructed wetland were obviously better than that in the single layer system, and the substrate effective utilization rates were 0.87 and 0.49, respectively. It was appeared that numerical simulation would be favorable for substrate structure optimization in subsurface flow constructed wetlands.

Characterization of double diffusive convection step and heat budget in the deep Arctic Ocean

NASA Astrophysics Data System (ADS)

Zhou, S.; Lu, Y.

2013-12-01

In this paper, we explore the hydrographic structure and heat budget in deep Canada Basin using data measured with McLane-Moored-Profilers (MMPs), bottom-pressure-recorders (BPRs), and conductivity-temperature-depth (CTD) profilers. From the bottom upward, a homogenous bottom layer and its overlaying double diffusive convection (DDC) steps are well identified at Mooring A (75oN, 150oW). We find that the deep water is in weak diapycnal mixing because the effective diffusivity of the bottom layer is ~1.8×10-5 m 2s-1 while that of the other steps is ~10-6 m 2s-1. The vertical heat flux through DDC steps is evaluated with different methods. We find that the heat flux (0.1-11 mWm-2) is much smaller than geothermal heating (~50 mWm-2), which suggests that the stack of DDC steps acts as a thermal barrier in the deep basin. Moreover, the temporal distributions of temperature and salinity differences across the interface are exponential, while those of heat flux and effective diffusivity are found to be approximately log-normal. Both are the result of strong intermittency. Between 2003 and 2011, temperature fluctuation close to the sea floor distributed asymmetrically and skewed towards positive values, which provides direct indication that geothermal heating is transferred into ocean. Both BPR and CTD data suggest that geothermal heating, not the warming of upper ocean, is the dominant mechanism responsible for the warming of deep water. As the DDC steps prevent the vertical heat transfer, geothermal heating will be unlikely to have significant effect on the middle and upper oceans.

Characterization of double diffusive convection steps and heat budget in the deep Arctic Ocean

NASA Astrophysics Data System (ADS)

Zhou, Sheng-Qi; Lu, Yuan-Zheng

2013-12-01

In this paper, we explore the hydrographic structure and heat budget in the deep Canada Basin by using data measured with McLane-Moored-Profilers (MMP), bottom pressure recorders (BPR), and conductivity-temperature-depth (CTD) profilers. Upward from the bottom, a homogeneous bottom layer and its overlaying double diffusive convection (DDC) steps are well identified at Mooring A (75°N,150°W). We find that the deep water is in weak diapycnal mixing because the effective diffusivity of the bottom layer is ˜1.8 × 10-5 m2s-1, while that of the other steps is ˜10-6 m2s-1. The vertical heat flux through the DDC steps is evaluated by using different methods. We find that the heat flux (0.1-11 mWm -2) is much smaller than geothermal heating (˜50 mWm -2). This suggests that the stack of DDC steps acts as a thermal barrier in the deep basin. Moreover, the temporal distributions of temperature and salinity differences across the interface are exponential, whereas those of heat flux and effective diffusivity are found to be approximately lognormal. Both are the result of strong intermittency. Between 2003 and 2011, temperature fluctuations close to the sea floor were distributed asymmetrically and skewed toward positive values, which provide a direct observation that geothermal heating was transferred into the ocean. Both BPR and CTD data suggest that geothermal heating and not the warming of the upper ocean is the dominant mechanism responsible for the warming of deep water. As the DDC steps prevent vertical heat transfer, geothermal heating is unlikely to have a significant effect on the middle and upper Arctic Ocean.

Barriers to Quitting Smoking among Substance Dependent Patients Predict Smoking Cessation Treatment Outcome

PubMed Central

Martin, Rosemarie A.; Cassidy, Rachel; Murphy, Cara M.; Rohsenow, Damaris J.

2016-01-01

For smokers with substance use disorders (SUD), perceived barriers to quitting smoking include concerns unique to effects on sobriety as well as usual concerns. We expanded our Barriers to Quitting Smoking in Substance Abuse Treatment (BQS-SAT) scale, added importance ratings, validated it, and then used the importance scores to predict smoking treatment response in smokers with substance use disorders (SUD) undergoing smoking treatment in residential treatment programs in two studies (n = 184 and 340). Both components (General Barriers, Weight Concerns) were replicated with excellent internal consistency reliability. Construct validity was supported by significant correlations with pretreatment nicotine dependence, smoking variables, smoking self-efficacy, and expected effects of smoking. General Barriers significantly predicted 1-month smoking abstinence, frequency and heaviness, and 3-month smoking frequency; Weight Concerns predicted 1-month smoking frequency. Implications involve addressing barriers with corrective information in smoking treatment for smokers with SUD. PMID:26979552

Barriers to Quitting Smoking Among Substance Dependent Patients Predict Smoking Cessation Treatment Outcome.

PubMed

Martin, Rosemarie A; Cassidy, Rachel N; Murphy, Cara M; Rohsenow, Damaris J

2016-05-01

For smokers with substance use disorders (SUD), perceived barriers to quitting smoking include concerns unique to effects on sobriety as well as usual concerns. We expanded our Barriers to Quitting Smoking in Substance Abuse Treatment (BQS-SAT) scale, added importance ratings, validated it, and then used the importance scores to predict smoking treatment response in smokers with substance use disorders (SUD) undergoing smoking treatment in residential treatment programs in two studies (n=184 and 340). Both components (general barriers, weight concerns) were replicated with excellent internal consistency reliability. Construct validity was supported by significant correlations with pretreatment nicotine dependence, smoking variables, smoking self-efficacy, and expected effects of smoking. General barriers significantly predicted 1-month smoking abstinence, frequency and heaviness, and 3-month smoking frequency; weight concerns predicted 1-month smoking frequency. Implications involve addressing barriers with corrective information in smoking treatment for smokers with SUD. Copyright © 2016 Elsevier Inc. All rights reserved.

Psychometrics of A New Questionnaire to Assess Glaucoma Adherence: The Glaucoma Treatment Compliance Assessment Tool (An American Ophthalmological Society Thesis)

PubMed Central

Mansberger, Steven L.; Sheppler, Christina R.; McClure, Tina M.; VanAlstine, Cory L.; Swanson, Ingrid L.; Stoumbos, Zoey; Lambert, William E.

2013-01-01

Purpose: To report the psychometrics of the Glaucoma Treatment Compliance Assessment Tool (GTCAT), a new questionnaire designed to assess adherence with glaucoma therapy. Methods: We developed the questionnaire according to the constructs of the Health Belief Model. We evaluated the questionnaire using data from a cross-sectional study with focus groups (n = 20) and a prospective observational case series (n=58). Principal components analysis provided assessment of construct validity. We repeated the questionnaire after 3 months for test-retest reliability. We evaluated predictive validity using an electronic dosing monitor as an objective measure of adherence. Results: Focus group participants provided 931 statements related to adherence, of which 88.7% (826/931) could be categorized into the constructs of the Health Belief Model. Perceived barriers accounted for 31% (288/931) of statements, cues-to-action 14% (131/931), susceptibility 12% (116/931), benefits 12% (115/931), severity 10% (91/931), and self-efficacy 9% (85/931). The principal components analysis explained 77% of the variance with five components representing Health Belief Model constructs. Reliability analyses showed acceptable Cronbach’s alphas (>.70) for four of the seven components (severity, susceptibility, barriers [eye drop administration], and barriers [discomfort]). Predictive validity was high, with several Health Belief Model questions significantly associated (P <.05) with adherence and a correlation coefficient (R2) of .40. Test-retest reliability was 90%. Conclusion: The GTCAT shows excellent repeatability, content, construct, and predictive validity for glaucoma adherence. A multisite trial is needed to determine whether the results can be generalized and whether the questionnaire accurately measures the effect of interventions to increase adherence. PMID:24072942

Refining Measurement of Social Cognitive Theory Factors Associated with Exercise Adherence in Head and Neck Cancer Patients.

PubMed

Rogers, Laura Q; Fogleman, Amanda; Verhulst, Steven; Bhugra, Mudita; Rao, Krishna; Malone, James; Robbs, Randall; Robbins, K Thomas

2015-01-01

Social cognitive theory (SCT) measures related to exercise adherence in head and neck cancer (HNCa) patients were developed. Enrolling 101 HNCa patients, psychometric properties and associations with exercise behavior were examined for barriers self-efficacy, perceived barriers interference, outcome expectations, enjoyment, and goal setting. Cronbach's alpha ranged from.84 to.95; only enjoyment demonstrated limited test-retest reliability. Subscales for barriers self-efficacy (motivational, physical health) and barriers interference (motivational, physical health, time, environment) were identified. Multiple SCT constructs were cross-sectional correlates and prospective predictors of exercise behavior. These measures can improve the application of the SCT to exercise adherence in HNCa patients.

Research on Livable Community Evaluation Based on GIS

NASA Astrophysics Data System (ADS)

Yin, Zhangcai; Wu, Yang; Jin, Zhanghaonan; Zhang, Xu

2018-01-01

Community is the basic unit of the city. Research on livable community could provide a bottom-up research path for the realization of livable city. Livability is the total factor affecting the quality of community life. In this paper, livable community evaluation indexes are evaluated based on GIS and fuzzy comprehensive evaluation method. Then the sum-index and sub-index of community livability are both calculated. And community livable evaluation index system is constructed based on the platform of GIS. This study provides theoretical support for the construction and management of livable communities, so as to guide the development and optimization of city.

GENESUS: a two-step sequence design program for DNA nanostructure self-assembly.

PubMed

Tsutsumi, Takanobu; Asakawa, Takeshi; Kanegami, Akemi; Okada, Takao; Tahira, Tomoko; Hayashi, Kenshi

2014-01-01

DNA has been recognized as an ideal material for bottom-up construction of nanometer scale structures by self-assembly. The generation of sequences optimized for unique self-assembly (GENESUS) program reported here is a straightforward method for generating sets of strand sequences optimized for self-assembly of arbitrarily designed DNA nanostructures by a generate-candidates-and-choose-the-best strategy. A scalable procedure to prepare single-stranded DNA having arbitrary sequences is also presented. Strands for the assembly of various structures were designed and successfully constructed, validating both the program and the procedure.

Prediabetes Screening and Treatment in Diabetes Prevention: The Impact of Physician Attitudes.

PubMed

Mainous, Arch G; Tanner, Rebecca J; Scuderi, Christopher B; Porter, Maribeth; Carek, Peter J

Detection and treatment of prediabetes is an effective strategy in diabetes prevention. However, most patients with prediabetes are not identified. Our objective was to evaluate the relationship between attitudes toward prediabetes as a clinical construct and screening/treatment behaviors for diabetes prevention among US family physicians. An electronic survey of a national sample of academic family physicians (n 1248) was conducted in 2016. Attitude toward prediabetes was calculated using a summated scale assessing agreement with statements regarding prediabetes as a clinical construct. Perceived barriers to diabetes prevention, current strategies for diabetes prevention, and perceptions of peers were also examined. Physicians who have a positive attitude toward prediabetes as a clinical construct are more likely to follow national guidelines for screening (58.4% vs 44.4; P < .0001) and recommend metformin to their patients for prediabetes (36.4% vs 20.9%; P < .0001). Physicians perceived a number of barriers to treatment, including a patient's economic resources (71.9%), sustaining patient motivation (83.2%), a patient's ability to modify his or her lifestyle (75.3%), and time to educate patient (75.3%) as barriers to diabetes prevention. How physicians view prediabetes varies significantly, and this variation is related to treatment/screening behaviors for diabetes prevention. © Copyright 2016 by the American Board of Family Medicine.

Roll-to-roll suitable short-pulsed laser scribing of organic photovoltaics and close-to-process characterization

NASA Astrophysics Data System (ADS)

Kuntze, Thomas; Wollmann, Philipp; Klotzbach, Udo; Fledderus, Henri

2017-03-01

The proper long term operation of organic electronic devices like organic photovoltaics OPV depends on their resistance to environmental influences such as permeation of water vapor. Major efforts are spent to encapsulate OPV. State of the art is sandwich-like encapsulation between two ultra-barrier foils. Sandwich encapsulation faces two major disadvantages: high costs ( 1/3 of total costs) and parasitic intrinsic water (sponge effects of the substrate foil). To fight these drawbacks, a promising approach is to use the OPV substrate itself as barrier by integration of an ultra-barrier coating, followed by alternating deposition and structuring of OPV functional layers. In effect, more functionality will be integrated into less material, and production steps are reduced in number. All processing steps must not influence the underneath barrier functionality, while all electrical functionalities must be maintained. As most reasonable structuring tool, short and ultrashort pulsed lasers USP are used. Laser machining applies to three layers: bottom electrode made of transparent conductive materials (P1), organic photovoltaic operative stack (P2) and top electrode (P3). In this paper, the machining of functional 110…250 nm layers of flexible OPV by USP laser systems is presented. Main focus is on structuring without damaging the underneath ultra-barrier layer. The close-to-process machining quality characterization is performed with the analysis tool "hyperspectral imaging" (HSI), which is checked crosswise with the "gold standard" Ca-test. It is shown, that both laser machining and quality controlling, are well suitable for R2R production of OPV.

34 CFR 1200.151 - Program accessibility: New construction and alterations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 34 Education 3 2010-07-01 2010-07-01 false Program accessibility: New construction and alterations. 1200.151 Section 1200.151 Education Regulations of the Offices of the Department of Education... standards of the Architectural Barriers Act (42 U.S.C. 4151-4157), as established in 41 CFR 101-19.600 to...

EFFECTIVE REMOVAL OF TCE IN A LABORATORY MODEL OF A PRB CONSTRUCTED WITH PLANT MULCH

EPA Science Inventory

Ground water contaminated with TCE is commonly treated with a permeable reactive barrier (PRB) constructed with zero-valence iron. The cost of iron as the reactive matrix has driven a search for less costly alternatives, and composted plant mulch has been used as an alternative ...

Mapping barriers and intervention activities to behaviour change theory for Mobilization of Vulnerable Elders in Ontario (MOVE ON), a multi-site implementation intervention in acute care hospitals.

PubMed

Moore, Julia E; Mascarenhas, Alekhya; Marquez, Christine; Almaawiy, Ummukulthum; Chan, Wai-Hin; D'Souza, Jennifer; Liu, Barbara; Straus, Sharon E

2014-10-30

As evidence-informed implementation interventions spread, they need to be tailored to address the unique needs of each setting, and this process should be well documented to facilitate replication. To facilitate the spread of the Mobilization of Vulnerable Elders in Ontario (MOVE ON) intervention, the aim of the current study is to develop a mapping guide that links identified barriers and intervention activities to behaviour change theory. Focus groups were conducted with front line health-care professionals to identify perceived barriers to implementation of an early mobilization intervention targeted to hospitalized older adults. Participating units then used or adapted intervention activities from an existing menu or developed new activities to facilitate early mobilization. A thematic analysis was performed on the focus group data, emphasizing concepts related to barriers to behaviour change. A behaviour change theory, the 'capability, opportunity, motivation-behaviour (COM-B) system', was used as a taxonomy to map the identified barriers to their root causes. We also mapped the behaviour constructs and intervention activities to overcome these. A total of 46 focus groups were conducted across 26 hospital inpatient units in Ontario, Canada, with 261 participants. The barriers were conceptualized at three levels: health-care provider (HCP), patient, and unit. Commonly mentioned barriers were time constraints and workload (HCP), patient clinical acuity and their perceived 'sick role' (patient), and lack of proper equipment and human resources (unit level). Thirty intervention activities to facilitate early mobilization of older adults were implemented across hospitals; examples of unit-developed intervention activities include the 'mobility clock' communication tool and the use of staff champions. A mapping guide was created with barriers and intervention activities matched though the lens of the COM-B system. We used a systematic approach to develop a guide, which maps barriers, intervention activities, and behaviour change constructs in order to tailor an implementation intervention to the local context. This approach allows implementers to identify potential strategies to overcome local-level barriers and to document adaptations.

Perceived barriers to reporting adverse drug events in hospitals: a qualitative study using theoretical domains framework approach.

PubMed

Mirbaha, Fariba; Shalviri, Gloria; Yazdizadeh, Bahareh; Gholami, Kheirollah; Majdzadeh, Reza

2015-08-07

Adverse drug events (ADEs) are a major source of morbidity and mortality, estimated as the forth to sixth cause of annual deaths in the USA. Spontaneous reporting of suspected ADEs by health care professionals to a national pharmacovigilance system is recognized as a useful method to detect and reduce harm from medicines; however, underreporting is a major drawback. Understanding the barriers to ADE reporting and thereafter design of interventions to increase ADE reporting requires a systematic approach and use of theory. Since multiple theories in behavior change exist that may have conceptually overlapping constructs, a group of experts suggested an integrative framework called theoretical domains framework (TDF). This approach considers a set of 12 domains, came from 33 theories and 128 constructs, covering the main factors influencing practitioner behavior and barriers to behavior change. The aim of this study is to apply TDF approach to establish an evidence-based understanding of barriers associated with ADE reporting among nurses and pharmacists. A total of three focus group discussions were conducted; among them two consisted of nurses and one involved pharmacists. Discussions were guided by questions designed based on TDF. Transcriptions of discussions were then thematically analyzed, and detected barriers to reporting ADEs were categorized based on extracted themes. A total of 34 nurses and pharmacists attended the group discussions. Six domains were identified to be relevant to barriers of ADE reporting in hospitals. These domains included "Knowledge," "Skills," "Beliefs about consequences," "Motivation and goals (intention)," "Social influences (norms)," and "Environmental constraints." We detected several barriers to ADE reporting, such as lack of knowledge of what should be reported, fear of punishment and criticism, lack of time, lack of teamwork, and lack of active support by hospital managements and other colleagues. Based on detected barriers, "Cognitive and behavioral factors," "Motivational factors and teamwork," in addition to "Organizational processes and resources" could be targeted in designing appropriate interventions. Detection of barriers to reporting ADEs is necessary to design appropriate interventions. The TDF is a comprehensive approach that enables us to better understand barriers to behavior change in reporting ADEs.

Apparatus and method for in Situ installation of underground containment barriers under contaminated lands

DOEpatents

Carter, Jr., Ernest E.; Sanford, Frank L.; Saugier, R. Kent

1999-09-28

An apparatus for constructing a subsurface containment barrier under a waste site disposed in soil is provided. The apparatus uses a reciprocating cutting and barrier forming device which forms a continuous elongate panel through the soil having a defined width. The reciprocating cutting and barrier forming device has multiple jets which eject a high pressure slurry mixture through an arcuate path or transversely across the panel being formed. A horizontal barrier can be formed by overlapping a plurality of such panels. The cutting device and barrier forming device is pulled through the soil by two substantially parallel pulling pipes which are directionally drilled under the waste site. A tractor or other pulling device is attached to the pulling pipes at one end and the cutting and barrier forming device is attached at the other. The tractor pulls the cutting and barrier forming device through the soil under the waste site without intersecting the waste site. A trailing pipe, attached to the cutting and barrier forming device, travels behind one of the pulling pipes. In the formation of an adjacent panel the trailing pipe becomes one of the next pulling pipes. This assures the formation of a continuous barrier.

Apparatus for in situ installation of underground containment barriers under contaminated lands

DOEpatents

Carter, Jr., Ernest E.; Sanford, Frank L.; Saugier, R. Kent

1998-06-16

An apparatus for constructing a subsurface containment barrier under a waste site disposed in soil is provided. The apparatus uses a reciprocating cutting and barrier forming device which forms a continuous elongate panel through the soil having a defined width. The reciprocating cutting and barrier forming device has multiple jets which eject a high pressure slurry mixture through an arcuate path or transversely across the panel being formed. A horizontal barrier can be formed by overlapping a plurality of such panels. The cutting device and barrier forming device is pulled through the soil by two substantially parallel pulling pipes which are directionally drilled under the waste site. A tractor or other pulling device is attached to the pulling pipes at one end and the cutting and barrier forming device is attached at the other. The tractor pulls the cutting and barrier forming device through the soil under the waste site without intersecting the waste site. A trailing pipe, attached to the cutting and barrier forming device, travels behind one of the pulling pipes. In the formation of an adjacent panel the trailing pipe becomes one of the next pulling pipes. This assures the formation of a continuous barrier.

Translation, Cross-cultural Adaptation and Psychometric Validation of the Korean-Language Cardiac Rehabilitation Barriers Scale (CRBS-K).

PubMed

Baek, Sora; Park, Hee-Won; Lee, Yookyung; Grace, Sherry L; Kim, Won-Seok

2017-10-01

To perform a translation and cross-cultural adaptation of the Cardiac Rehabilitation Barriers Scale (CRBS) for use in Korea, followed by psychometric validation. The CRBS was developed to assess patients' perception of the degree to which patient, provider and health system-level barriers affect their cardiac rehabilitation (CR) participation. The CRBS consists of 21 items (barriers to adherence) rated on a 5-point Likert scale. The first phase was to translate and cross-culturally adapt the CRBS to the Korean language. After back-translation, both versions were reviewed by a committee. The face validity was assessed in a sample of Korean patients (n=53) with history of acute myocardial infarction that did not participate in CR through semi-structured interviews. The second phase was to assess the construct and criterion validity of the Korean translation as well as internal reliability, through administration of the translated version in 104 patients, principle component analysis with varimax rotation and cross-referencing against CR use, respectively. The length, readability, and clarity of the questionnaire were rated well, demonstrating face validity. Analysis revealed a six-factor solution, demonstrating construct validity. Cronbach's alpha was greater than 0.65. Barriers rated highest included not knowing about CR and not being contacted by a program. The mean CRBS score was significantly higher among non-attendees (2.71±0.26) than CR attendees (2.51±0.18) (p<0.01). The Korean version of CRBS has demonstrated face, content and criterion validity, suggesting it may be useful for assessing barriers to CR utilization in Korea.

The Three Gorges Project: How sustainable?

NASA Astrophysics Data System (ADS)

Kepa Brian Morgan, Te Kipa; Sardelic, Daniel N.; Waretini, Amaria F.

2012-08-01

SummaryIn 1984 the Government of China approved the decision to construct the Three Gorges Dam Project, the largest project since the Great Wall. The project had many barriers to overcome, and the decision was made at a time when sustainability was a relatively unknown concept. The decision to construct the Three Gorges Project remains contentious today, especially since Deputy Director of the Three Gorges Project Construction Committee, Wang Xiaofeng, stated that "We absolutely cannot relax our guard against ecological and environmental security problems sparked by the Three Gorges Project" (Bristow, 2007; McCabe, 2007). The question therefore was posed: how sustainable is the Three Gorges Project? Conventional approaches to sustainability assessment tend to use monetary based assessment aligned to triple bottom line thinking. That is, projects are evaluated as trade-offs between economic, environmental and social costs and benefits. The question of sustainability is considered using such a traditional Cost-Benefit Analysis approach, as undertaken in 1988 by a CIPM-Yangtze Joint Venture, and the Mauri Model Decision Making Framework (MMDMF). The Mauri Model differs from other approaches in that sustainability performance indicators are considered independently from any particular stakeholder bias. Bias is then introduced subsequently as a sensitivity analysis on the raw results obtained. The MMDMF is unique in that it is based on the Māori concept of Mauri, the binding force between the physical and the spiritual attributes of something, or the capacity to support life in the air, soil, and water. This concept of Mauri is analogous to the Chinese concept of Qi, and there are many analogous concepts in other cultures. It is the universal relevance of Mauri that allows its use to assess sustainability. This research identified that the MMDMF was a strong complement to Cost-Benefit Analysis, which is not designed as a sustainability assessment tool in itself. The MMDMF does have relevance in identifying areas of conflict, and it can support the Cost-Benefit Analysis in assessing sustainability, as a Decision Support Tool. The research concluded that, based on both models, the Three Gorges Project as understood in 1988, and incorporating more recent sustainability analysis is contributing to enhanced sustainability.

The Positive Role of Negative Emotions: Fear, Anxiety, Conflict and Resistance as Productive Experiences in Academic Study and in the Emergence of Learner Autonomy

ERIC Educational Resources Information Center

Kannan, Jaya; Miller, John Laurence

2009-01-01

Although affect is widely recognized as a powerful force in determining students' academic success, researchers and practitioners have paid little attention to emotional barriers that often impede college success or how instructors may respond constructively when such barriers arise. The purpose of this paper is to initiate discussion of this…

Bond behavior of self compacting concrete

NASA Astrophysics Data System (ADS)

Ponmalar, S.

2018-03-01

The success of an optimum design lies in the effective load transfer done by the bond forces at the steel-concrete interface. Self Compacting Concrete, is a new innovative concrete capable of filling intrinsic reinforcement and gets compacted by itself, without the need of external mechanical vibration. For this reason, it is replacing the conventional vibrated concrete in the construction industry. The present paper outlays the materials and methods adopted for attaining the self compacting concrete and describes about the bond behavior of this concrete. The bond stress-slip curve is similar in the bottom bars for both SCC and normal concrete whereas a higher bond stress and stiffness is experienced in the top and middle bars, for SCC compared to normal concrete. Also the interfacial properties revealed that the elastic modulus and micro-strength of interfacial transition zone [ITZ] were better on the both top and bottom side of horizontal steel bar in the SCC mixes than in normal vibrated concrete. The local bond strength of top bars for SCC is about 20% less than that for NC. For the bottom bars, however, the results were almost the same.

Conversion of coal-fired bottom ash to fuel and construction materials.

PubMed

Koca, Huseyin; Aksoy, Derya Oz; Ucar, Reyhan; Koca, Sabiha

2017-07-01

In this study, solid wastes taken from Seyitomer coal-fired power plant bottom ashes were subjected to experimental research to obtain a carbon-rich fraction. The possible recycling opportunities of remaining inorganic fraction in the cement and concrete industry was also investigated. Flotation technique was used to separate unburned carbon from inorganic bottom ashes. Collector type, collector, dispersant and frother amounts, and pulp density are the most important variables in the flotation technique. A number of flotation collectors were tested in the experiments including new era flotation reactives. Optimum collector, dispersant and frother dosages as well as optimum pulp density were also determined. After experimental work, an inorganic fraction was obtained, which included 5.41% unburned carbon with 81.56% weight yield. These properties meets the industrial specifications for the cement and concrete industry. The carbon content of the concentrate fraction, obtained in the same experiment, was enhanced to 49.82%. This fraction accounts for 18.44% of the total amount and can be mixed to the power plant fuel. Therefore total amount of the solid waste can possibly be recycled according to experimental results.

Reconnaissance of water quality of Pueblo Reservoir, Colorado: May through December 1985

USGS Publications Warehouse

Edelmann, Patrick

1989-01-01

Pueblo Reservoir is the farthest upstream, main-stream reservoir constructed on the Arkansas River and is located in Pueblo County approximately 6 miles upstream from the city of Pueblo, Colorado. During the 1985 sampling period, the reservoir was stratified, and underflow from the Arkansas River occurred that resulted in stratification with respect to specific conductance. Concentrations of dissolved solids decreased markedly below the thermocline during June. Later in the summer, dissolved-solids concentrations increased substantially below the thermocline. Substantial depletion of dissolved oxygen occurred near the bottom of the reservoir. The dissolved oxygen minimum of 0.1 mg/L occurred during August near the reservoir bottom at transect 7 (near the dam). The average total-inorganic-nitrogen concentration near the reservoir surface was about 0.2 mg/L; near the reservoir bottom, the average concentration was about 0.3 mg/L. Concentrations of total phosphorus ranged from less than 0.01 to 0.05 mg/L near the reservoir surface, and from less than 0.01 to 0.22 mg/L near the reservoir bottom. At transect 2 (about 7 miles upstream from the dam) near the bottom of the reservoir, concentrations of total iron exceeded aquatic-life standards, and dissolved-manganese concentrations exceeded standards for public water supply. Diatoms, green algae, blue-green algae, and cryptomonads comprised the majority of phytoplankton in Pueblo Reservoir in 1985. The maximum average of 41,000 cells/ml occurred in July. Blue-green algae dominated from June to September; diatoms were the dominant group of algae in October. The average concentrations of phytoplankton decreased from July to October. (USGS)

Capital intensity of photovoltaics manufacturing: Barrier to scale and opportunity for innovation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Powell, Douglas M.; Fu, Ran; Horowitz, Kelsey

In this study, using a bottom-up cost model, we assess the impact of initial factory capital expenditure (capex) on photovoltaic (PV) module minimum sustainable price (MSP) and industry-wide trends. We find capex to have two important impacts on PV manufacturing. First, capex strongly influences the per-unit MSP of a c-Si module: we calculate that the capex-related elements sum to 22% of MSP for an integrated wafer, cell, and module manufacturer. This fraction provides a significant opportunity to reduce MSP toward the U.S. DOE SunShot module price target through capex innovation.

Expanding Role of Data Science and Bioinformatics in Drug Discovery and Development.

PubMed

Fingert, Howard J

2018-01-01

Numerous barriers have been identified which detract from successful applications of clinical trial data and platforms. Despite the challenges, opportunities are growing to advance compliance, quality, and practical applications through top-down establishment of guiding principles, coupled with bottom-up approaches to promote data science competencies among data producers. Recent examples of successful applications include modern treatments for hematologic malignancies, developed with support from public-private partnerships, guiding principles for data-sharing, standards for protocol designs and data management, digital technologies, and quality analytics. © 2017 American Society for Clinical Pharmacology and Therapeutics.

Capital intensity of photovoltaics manufacturing: Barrier to scale and opportunity for innovation

DOE PAGES

Powell, Douglas M.; Fu, Ran; Horowitz, Kelsey; ...

2015-09-07

In this study, using a bottom-up cost model, we assess the impact of initial factory capital expenditure (capex) on photovoltaic (PV) module minimum sustainable price (MSP) and industry-wide trends. We find capex to have two important impacts on PV manufacturing. First, capex strongly influences the per-unit MSP of a c-Si module: we calculate that the capex-related elements sum to 22% of MSP for an integrated wafer, cell, and module manufacturer. This fraction provides a significant opportunity to reduce MSP toward the U.S. DOE SunShot module price target through capex innovation.

"State of the Art" of technical protection measures in Austria and the effectiveness documented during bedload and debris flow events

NASA Astrophysics Data System (ADS)

Moser, Markus; Mehlhorn, Susanne; Rudolf-Miklau, Florian; Suda, Jürgen

2017-04-01

Since the beginning of systematic torrent control in Austria 130 years ago, barriers are constructed for protection purposes. Until the end of the 1960s, solid barriers were built at the exits of depositional areas to prevent dangerous debris flows from reaching high consequence areas. The development of solid barriers with large slots or slits to regulate sediment transport began with the use of reinforced concrete during the 1970s (Rudolf-Miklau, Suda 2011). In order to dissipate the energy of debris flows debris flow breakers have been designed since the 1980s. By slowing and depositing the surge front of the debris flow, downstream reaches of the stream channel and settlement areas should be exposed to considerably lower dynamic impact. In the past, the technological development of these constructions was only steered by the experiences of the engineering practice while an institutionalized process of standardization comparable to other engineering branches was not existent. In future all structures have to be designed and dimensioned according to the EUROCODE standards. This was the reason to establish an interdisciplinary working group (ON-K 256) at the Austrian Standards Institute (ASI), which has managed to developed comprehensive new technical standards for torrent control engineering, including load models, design, dimensioning and life cycle assessment of torrent control works (technical standard ONR 24800 - series). Extreme torrential events comprise four definable displacement processes floods; fluvial solid transport; hyper-concentrated solid transport (debris floods) and debris flow (stony debris flow or mud-earth flow). As a rule, the design of the torrential barriers has to follow its function (Kettl, 1984). Modern protection concepts in torrent control are scenario-oriented and try to optimize different functions in a chain of protections structures (function chain). More or less the first step for the designing the optimal construction type is the definition of the displacement processes for each torrent section. The criteria for each process are defined in the technical standard ONR 24800 - series in Austria. According to ONR 24800 the functions of torrential barriers can be divided in process control functional types (retention; dosing and filtering; energy dissipation). The last step is the designing of the construction type. Bedload and debris events in Austria showed the functionality of the barriers. On the basis of these findings and results, some recommendations were derived to improve the function fulfilment of the technical protection measures.

An investigation into variable recharge behaviors among eight alluvial observation wells in Pajarito Canyon, Los Alamos, New Mexico

NASA Astrophysics Data System (ADS)

Schmeer, S. R.

2010-12-01

Pajarito Canyon in Los Alamos, New Mexico trends west to east through the Pajarito Plateau from the headwaters in the Jemez Mountains, thirteen miles to the Rio Grande. In summer 2008, Los Alamos National Laboratory installed eight shallow wells, numbered PCAO-5, 6, 7a, 7b1, 7b2, 7c, 8 and 9, in the middle four miles of this canyon. Among these wells, five distinct recharge behaviors have been observed. PCAO-5 demonstrates seasonal recharge in response to annual snowmelt. PCAO-6, while just 400 feet further downstream, is considerably flashier and the well is often dry for months at a time. In PCAO-7a, 7b2 and 7c, another two miles downstream, the water level declined steadily since installation, with no recharge until spring 2010. PCAO-7b1 has not contained water since drilling. Downstream a further two miles, PCAO-8 and PCAO-9 were dry for the majority of 2009 and their hydrographs are more attenuated. This investigation was undertaken to explain the recharge behaviors of the wells, with the goal of improving site selection and design of alluvial wells to provide better representation of the alluvial aquifer. Water level data collected since July 2008 were used to compare the water columns of each well. Well construction diagrams were utilized to construct stratigraphic maps in order to compare well construction and lithology. Results indicate that PCAO-5 consistently contains water due to its location above a flood retention structure (FRS) and the placement of its screened interval immediately above the tuff layer, forcing water to travel through the screened interval. PCAO-6’s flashy, intermittent hydrograph is due to its location downstream of the FRS, and because the bottom of the screened interval rests 2.5 feet above the alluvium-tuff interface, providing a conduit below the screen of the well. The similar behaviors of PCAO-7a, 7b2 and 7c result from their near-identical construction, lithology and location. The general decline of water level until spring 2010 was due to near-drought conditions in 2009. PCAO-7a retained more water more consistently through 2009 because its screened interval rests on the alluvium-tuff interface, whereas PCAO-7b2 and 7c are both screened similarly to PCAO-6. PCAO-7b1, which has not contained water since drilling, has its screened interval within the tuff later, preventing alluvial groundwater from reaching the screen. The attenuated hydrographs of PCAO-8 and 9 are possibly due to their downstream location; in the semi-arid study area, much of the alluvial groundwater sourced in the mountains may already have infiltrated towards the deeper aquifers before reaching the lower portion of the canyon. These results indicate that shallow wells in areas with a lithology similar to the study area should be constructed with a screened interval that rests directly on the alluvium-tuff interface, thereby forcing flow through the screen. Additionally, deep barriers such as the FRS will greatly inhibit consistent flow of alluvial groundwater into shallow wells built immediately downstream of the barrier. Finally, shallow wells in the lower portions of semi-arid canyons may not consistently contain water because source water from the mountains may infiltrate too deep before reaching the wells.

39 CFR 776.8 - Scope.

Code of Federal Regulations, 2010 CFR

2010-07-01

... trails, or boardwalks, including signs, the primary purposes of which are public education... Architectural Barriers Act or postal accessibility standards; (3) Any facility construction project deemed...

Sacrificial Girls: A Case Study of the Impact of Streaming and Setting on Gender Reform

ERIC Educational Resources Information Center

Charlton, Emma; Mills, Martin; Martino, Wayne; Beckett, Lori

2007-01-01

This article reports on research funded by the Australian Research Council to investigate school responses to gender equity. It addresses the efforts of a disadvantaged school to tackle what they perceived to be gender inequalities, but in the process of constructing a top-set and bottom-set/stream class they are developing new forms of old…

76 FR 13363 - Intent To Prepare an Environmental Impact Statement for the Port of Gulfport Expansion Project...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-11

... application filed on March 17, 2010, proposed filling approximately 700 acres of open-water benthic habitat... filling of up to 400 acres of open-water bottom in the Mississippi Sound, the construction of wharfs... the USACE in deciding whether to issue a Department of the Army permit. The purpose of this Notice of...

33 CFR 165.T01-0329 - Regulated Navigation Area; Maine Kennebec Bridge Construction and Removal, Kennebec River...

Code of Federal Regulations, 2014 CFR

2014-07-01

... notice, as well as Broadcast Notice to Mariners and Local Notice to Mariners. (2) Violations of this RNA... Regulated Navigation Area (RNA): All navigable waters, surface to bottom, on the Kennebec River within a 300....11 and 165.13 apply within the RNA. (2) In accordance with the general regulations, entry into or...

Geochemical anomalies from bottom ash in a road construction--comparison of the leaching potential between an ash road and the surroundings.

PubMed

Lind, Bo B; Norrman, Jenny; Larsson, Lennart B; Ohlsson, Sten-Ake; Bristav, Henrik

2008-01-01

A study was performed between June 2001 and December 2004 with the primary objective of assessing long-term leaching from municipal solid waste incineration bottom ash in a test road construction in relation to a reference road made up of conventional materials and the natural geochemical conditions in the surroundings. The metal leaching from the test road and the reference road was compared with the natural weathering in the regional surroundings for three time scales: 16, 80 and 1000 years. The results show that Cu and Zn cause a geochemical anomaly from the test road compared with the surroundings. The leaching of Cu from the test road is initially high but will decline with time and will in the long term be exceeded by natural weathering. Zn on the other hand has low initial leaching, which will increase with time and will in the long term exceed that of the test road and the surroundings by a factor of 100-300. For the other metals studied, Al, Na, K and Mg, there is only very limited leaching over time and the potential accumulation will not exceed the background values in a 1000 years.

Top mass from asymptotic safety

NASA Astrophysics Data System (ADS)

Eichhorn, Astrid; Held, Aaron

2018-02-01

We discover that asymptotically safe quantum gravity could predict the top-quark mass. For a broad range of microscopic gravitational couplings, quantum gravity could provide an ultraviolet completion for the Standard Model by triggering asymptotic freedom in the gauge couplings and bottom Yukawa and asymptotic safety in the top-Yukawa and Higgs-quartic coupling. We find that in a part of this range, a difference of the top and bottom mass of approximately 170GeV is generated and the Higgs mass is determined in terms of the top mass. Assuming no new physics below the Planck scale, we construct explicit Renormalization Group trajectories for Standard Model and gravitational couplings which link the transplanckian regime to the electroweak scale and yield a top pole mass of Mt,pole ≈ 171GeV.

Monolayer borophene electrode for effective elimination of both the Schottky barrier and strong electric field effect

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, L. Z., E-mail: lzliu@nju.edu.cn, E-mail: hkxlwu@nju.edu.cn; Xiong, S. J.; Wu, X. L., E-mail: lzliu@nju.edu.cn, E-mail: hkxlwu@nju.edu.cn

2016-08-08

The formation of Schottky barriers between 2D semiconductors and traditional metallic electrodes has greatly limited the application of 2D semiconductors in nanoelectronic and optoelectronic devices. In this study, metallic borophene was used as a substitute for the traditional noble metal electrode to contact with the 2D semiconductor. Theoretical calculations demonstrated that no Schottky barrier exists in the borophene/2D semiconductor heterostructure. The contact remains ohmic even with a strong electric field applied. This finding provides a way to construct 2D electronic devices and sensors with greatly enhanced performance.

How can we teach EBM in clinical practice? An analysis of barriers to implementation of on-the-job EBM teaching and learning.

PubMed

Oude Rengerink, Katrien; Thangaratinam, Shakila; Barnfield, Gemma; Suter, Katja; Horvath, Andrea R; Walczak, Jacek; Wełmińska, Anna; Weinbrenner, Susanne; Meyerrose, Berit; Arvanitis, Theodoros N; Onody, Rita; Zanrei, Gianni; Kunz, Regina; Arditi, Chantal; Burnand, Bernard; Gee, Harry; Khan, Khalid S; Mol, Ben W J

2011-01-01

Evidence-based medicine (EBM) improves the quality of health care. Courses on how to teach EBM in practice are available, but knowledge does not automatically imply its application in teaching. We aimed to identify and compare barriers and facilitators for teaching EBM in clinical practice in various European countries. A questionnaire was constructed listing potential barriers and facilitators for EBM teaching in clinical practice. Answers were reported on a 7-point Likert scale ranging from not at all being a barrier to being an insurmountable barrier. The questionnaire was completed by 120 clinical EBM teachers from 11 countries. Lack of time was the strongest barrier for teaching EBM in practice (median 5). Moderate barriers were the lack of requirements for EBM skills and a pyramid hierarchy in health care management structure (median 4). In Germany, Hungary and Poland, reading and understanding articles in English was a higher barrier than in the other countries. Incorporation of teaching EBM in practice faces several barriers to implementation. Teaching EBM in clinical settings is most successful where EBM principles are culturally embedded and form part and parcel of everyday clinical decisions and medical practice.

Rocket Motor Joint Construction Including Thermal Barrier

NASA Technical Reports Server (NTRS)

Steinetz, Bruce M. (Inventor); Dunlap, Patrick H., Jr. (Inventor)

2002-01-01

A thermal barrier for extremely high temperature applications consists of a carbon fiber core and one or more layers of braided carbon fibers surrounding the core. The thermal barrier is preferably a large diameter ring, having a relatively small cross-section. The thermal barrier is particularly suited for use as part of a joint structure in solid rocket motor casings to protect low temperature elements such as the primary and secondary elastomeric O-ring seals therein from high temperature gases of the rocket motor. The thermal barrier exhibits adequate porosity to allow pressure to reach the radially outward disposed O-ring seals allowing them to seat and perform the primary sealing function. The thermal barrier is disposed in a cavity or groove in the casing joint, between the hot propulsion gases interior of the rocket motor and primary and secondary O-ring seals. The characteristics of the thermal barrier may be enhanced in different applications by the inclusion of certain compounds in the casing joint, by the inclusion of RTV sealant or similar materials at the site of the thermal barrier, and/or by the incorporation of a metal core or plurality of metal braids within the carbon braid in the thermal barrier structure.

Validity of a Competing Food Choice Construct regarding Fruit and Vegetable Consumption among Urban College Freshmen

ERIC Educational Resources Information Center

Yeh, Ming-Chin; Matsumori, Brandy; Obenchain, Janel; Viladrich, Anahi; Das, Dhiman; Navder, Khursheed

2010-01-01

Objective: This paper presents the reliability and validity of a "competing food choice" construct designed to assess whether factors related to consumption of less-healthful food were perceived to be barriers to fruit and vegetable consumption in college freshmen. Design: Cross-sectional, self-administered survey. Setting: An urban public college…

Mechanical properties of gypsum board at elevated temperatures

Treesearch

S.M. Cramer; O.M. Friday; R.H. White; G. Sriprutkiat

2003-01-01

Gypsum board is a common fire barrier used in house and general building construction. Recently, evaluation of the collapses of the World Trade Center Towers highlighted the potential role and failure of gypsum board in containing the fires and resisting damage. The use of gypsum board as primary fire protection of light-flame wood or steel construction is ubiquitous....

Statistical comparison of leaching behavior of incineration bottom ash using seawater and deionized water: Significant findings based on several leaching methods.

PubMed

Yin, Ke; Dou, Xiaomin; Ren, Fei; Chan, Wei-Ping; Chang, Victor Wei-Chung

2018-02-15

Bottom ashes generated from municipal solid waste incineration have gained increasing popularity as alternative construction materials, however, they contains elevated heavy metals posing a challenge for its free usage. Different leaching methods are developed to quantify leaching potential of incineration bottom ashes meanwhile guide its environmentally friendly application. Yet, there are diverse IBA applications while the in situ environment is always complicated, challenging its legislation. In this study, leaching tests were conveyed using batch and column leaching methods with seawater as opposed to deionized water, to unveil the metal leaching potential of IBA subjected to salty environment, which is commonly encountered when using IBA in land reclamation yet not well understood. Statistical analysis for different leaching methods suggested disparate performance between seawater and deionized water primarily ascribed to ionic strength. Impacts of leachant are metal-specific dependent on leaching methods and have a function of intrinsic characteristics of incineration bottom ashes. Leaching performances were further compared on additional perspectives, e.g. leaching approach and liquid to solid ratio, indicating sophisticated leaching potentials dominated by combined geochemistry. It is necessary to develop application-oriented leaching methods with corresponding leaching criteria to preclude discriminations between different applications, e.g., terrestrial applications vs. land reclamation. Copyright © 2017 Elsevier B.V. All rights reserved.

Construction and Characterization of a Novel Vocal Fold Bioreactor

PubMed Central

Zerdoum, Aidan B.; Tong, Zhixiang; Bachman, Brendan; Jia, Xinqiao

2014-01-01

In vitro engineering of mechanically active tissues requires the presentation of physiologically relevant mechanical conditions to cultured cells. To emulate the dynamic environment of vocal folds, a novel vocal fold bioreactor capable of producing vibratory stimulations at fundamental phonation frequencies is constructed and characterized. The device is composed of a function generator, a power amplifier, a speaker selector and parallel vibration chambers. Individual vibration chambers are created by sandwiching a custom-made silicone membrane between a pair of acrylic blocks. The silicone membrane not only serves as the bottom of the chamber but also provides a mechanism for securing the cell-laden scaffold. Vibration signals, generated by a speaker mounted underneath the bottom acrylic block, are transmitted to the membrane aerodynamically by the oscillating air. Eight identical vibration modules, fixed on two stationary metal bars, are housed in an anti-humidity chamber for long-term operation in a cell culture incubator. The vibration characteristics of the vocal fold bioreactor are analyzed non-destructively using a Laser Doppler Vibrometer (LDV). The utility of the dynamic culture device is demonstrated by culturing cellular constructs in the presence of 200-Hz sinusoidal vibrations with a mid-membrane displacement of 40 µm. Mesenchymal stem cells cultured in the bioreactor respond to the vibratory signals by altering the synthesis and degradation of vocal fold-relevant, extracellular matrix components. The novel bioreactor system presented herein offers an excellent in vitro platform for studying vibration-induced mechanotransduction and for the engineering of functional vocal fold tissues. PMID:25145349

Construction and characterization of a novel vocal fold bioreactor.

PubMed

Zerdoum, Aidan B; Tong, Zhixiang; Bachman, Brendan; Jia, Xinqiao

2014-08-01

In vitro engineering of mechanically active tissues requires the presentation of physiologically relevant mechanical conditions to cultured cells. To emulate the dynamic environment of vocal folds, a novel vocal fold bioreactor capable of producing vibratory stimulations at fundamental phonation frequencies is constructed and characterized. The device is composed of a function generator, a power amplifier, a speaker selector and parallel vibration chambers. Individual vibration chambers are created by sandwiching a custom-made silicone membrane between a pair of acrylic blocks. The silicone membrane not only serves as the bottom of the chamber but also provides a mechanism for securing the cell-laden scaffold. Vibration signals, generated by a speaker mounted underneath the bottom acrylic block, are transmitted to the membrane aerodynamically by the oscillating air. Eight identical vibration modules, fixed on two stationary metal bars, are housed in an anti-humidity chamber for long-term operation in a cell culture incubator. The vibration characteristics of the vocal fold bioreactor are analyzed non-destructively using a Laser Doppler Vibrometer (LDV). The utility of the dynamic culture device is demonstrated by culturing cellular constructs in the presence of 200-Hz sinusoidal vibrations with a mid-membrane displacement of 40 µm. Mesenchymal stem cells cultured in the bioreactor respond to the vibratory signals by altering the synthesis and degradation of vocal fold-relevant, extracellular matrix components. The novel bioreactor system presented herein offers an excellent in vitro platform for studying vibration-induced mechanotransduction and for the engineering of functional vocal fold tissues.

Sustainability assessment and prioritisation of bottom ash management in Macao.

PubMed

Sou, W I; Chu, Andrea; Chiueh, P T

2016-12-01

In Macao, about 7200 t yr -1 of bottom ash (BA) is generated and conventionally landfilled with construction waste. Because the properties of BA are similar to those of natural aggregates, it is suitable to be recycled as construction material. However, pre-treatment processes for BA reuse may require more resource input and may generate additional environmental impacts. Life cycle assessment, multi-media transport model analysis, cost-benefit analysis and the analytical hierarchy process were conducted to evaluate the impacts of current and potential BA management scenarios regarding environmental, economic, social and regulatory aspects. The five analysed scenarios are as follows: (0) BA buried with construction and demolition waste (current system); (1) pre-treated BA used to replace 25% of the natural aggregate in asphalt concrete; (2) pre-treated BA used to replace 25% of the natural aggregate in cement concrete; (3) pre-treated BA used to replace 25% of cement in cement concrete; and (4) pre-treated BA sent to China, blended with municipal solid waste for landfill. The results reveal the following ranking of the scenarios: 3 > 2 > 0 > 1 > 4. Scenario 3 shows the best conditions for BA recycling, because the quantity of cement concrete output is the highest and this brings the greatest economic benefits. Our use of integrated analysis provides multi-aspect investigations for BA management systems, particularly in accounting for site-specific characteristics. This approach is suitable for application in other non-western regions. © The Author(s) 2016.

On the origin of biological construction, with a focus on multicellularity.

PubMed

van Gestel, Jordi; Tarnita, Corina E

2017-10-17

Biology is marked by a hierarchical organization: all life consists of cells; in some cases, these cells assemble into groups, such as endosymbionts or multicellular organisms; in turn, multicellular organisms sometimes assemble into yet other groups, such as primate societies or ant colonies. The construction of new organizational layers results from hierarchical evolutionary transitions, in which biological units (e.g., cells) form groups that evolve into new units of biological organization (e.g., multicellular organisms). Despite considerable advances, there is no bottom-up, dynamical account of how, starting from the solitary ancestor, the first groups originate and subsequently evolve the organizing principles that qualify them as new units. Guided by six central questions, we propose an integrative bottom-up approach for studying the dynamics underlying hierarchical evolutionary transitions, which builds on and synthesizes existing knowledge. This approach highlights the crucial role of the ecology and development of the solitary ancestor in the emergence and subsequent evolution of groups, and it stresses the paramount importance of the life cycle: only by evaluating groups in the context of their life cycle can we unravel the evolutionary trajectory of hierarchical transitions. These insights also provide a starting point for understanding the types of subsequent organizational complexity. The central research questions outlined here naturally link existing research programs on biological construction (e.g., on cooperation, multilevel selection, self-organization, and development) and thereby help integrate knowledge stemming from diverse fields of biology.

Effect of elastic strain redistribution on electronic band structures of compressively strained GaInAsP/InP membrane quantum wires

NASA Astrophysics Data System (ADS)

Ferdous, F.; Haque, A.

2007-05-01

The effect of redistribution of elastic strain relaxation on the energy band structures of GaInAsP/InP compressively strained membrane quantum wires fabricated by electron-beam lithography, reactive-ion etching and two-step epitaxial growth is theoretically studied using an 8-band k ṡp method. Anisotropic strain analysis by the finite element method shows that due to etching away the top and the bottom InP clad layers in membrane structures, redistribution of strain occurs. It is found that strain redistribution increases the effective bandgap of membrane quantum wire structures causing a blueshift of the emission frequency. Comparison with effective bandgap calculations neglecting confinement and band mixing demonstrates that neglect of these effects leads to an overestimation of the change in the bandgap. We have also investigated the effect of variation of wire width, barrier strain compensation, number of stacked quantum wire layers, and thickness of the top and the bottom residual InP layers in membrane structures on the change in the effective bandgap of membrane structures.

Clay minerals in sediments of Portuguese reservoirs and their significance as weathering products from over-eroded soils: a comparative study of the Maranhão, Monte Novo and Divor Reservoirs (South Portugal)

NASA Astrophysics Data System (ADS)

Fonseca, Rita M. F.; Barriga, Fernando J. A. S.; Conceição, Patrícia I. S. T.

2010-12-01

The Southern region of Portugal is subjected to several forms of over-erosion. Most leached products, mainly composed of fine particles containing nutrients, metals or pesticides, are easily transported by river flows. When these are hindered by a physical barrier such as a dam, the particulate load accumulates on the bottom of the reservoirs, often leading to a pronounced decrease of water quality. Bottom sediments from three reservoirs were subjected to grain-size analysis and a study of clay minerals by X-ray diffraction. Most sediments contain a diverse set of clay minerals, mostly illites, smectites, chlorites and kaolinites. The nature of the clay minerals reflects the nature of the parent rocks. During the cycles of transport and temporary deposition, they may undergo significant chemical and physical transformations, which lead to an increase of expandable properties and therefore, to a higher cationic exchange capacity, determining its important role as vehicles of environmental pollutants.

Proposal of the confinement strategy of radioactive and hazardous materials for the European DEMO

NASA Astrophysics Data System (ADS)

Jin, X. Z.; Carloni, D.; Stieglitz, R.; Ciattaglia, S.; Johnston, J.; Taylor, N.

2017-04-01

Confinement of radioactive and hazardous materials is one of the fundamental safety functions in a nuclear fusion facility, which has to limit the mobilisation and dispersion of sources and hazards during normal, abnormal and accidental situations. In a first step energy sources and radioactive source have been assessed for a conceptual DEMO configuration. The confinement study for the European DEMO has been investigated for the main systems at the plant breakdown structure (PBS) level 1 taking a bottom-up approach. Based on the identification of the systems possessing a confinement function, a confinement strategy has been proposed, in which DEMO confinement systems and barriers have been defined. In addition, confinement for the maintenance has been issued as well. The assignment of confinement barriers to the identified sources under abnormal and accidental conditions has been performed, and the DEMO main safety systems have been proposed as well. Finally, confinement related open issues have been pointed out, which need to be resolved in parallel with DEMO development.

Influence of riffle characteristics, surficial geology, and natural barriers on the distribution of the channel darter, Percina copelandi, in the Lake Ontario basin

USGS Publications Warehouse

Reid, S.M.; Carl, L.M.; Lean, J.

2005-01-01

The channel darter, Percina copelandi, is a small benthic fish with a wide but disjunct distribution across central North America. The development of conservation and recovery strategies for Canadian populations is limited by a lack of knowledge regarding ecology, population size and other factors that affect its distribution and abundance. We sampled five rivers in the Lake Ontario basin to test whether the distribution of P. copelandi reflected riffle habitat characteristics or landscape-scale factors such as surficial geology and natural barriers (waterfalls). At most sites yielding P. copelandi, riffles flowed into deep sand bottomed run or pool habitats. Despite a lack of association with local surficial geology or riffle habitat characteristics, both the upstream limits of P. copelandi occurrence and distribution of suitable habitats reflected the distribution of waterfalls, chutes and bedrock outcroppings. In contrast to P. copelandi, distributions of Etheostoma flabellare, P. caprodes and Rhinichthys cataractae reflected among site differences in riffle habitat. ?? Springer 2005.

A physical model describing the interaction of nuclear transport receptors with FG nucleoporin domain assemblies

PubMed Central

Zahn, Raphael; Osmanović, Dino; Ehret, Severin; Araya Callis, Carolina; Frey, Steffen; Stewart, Murray; You, Changjiang; Görlich, Dirk; Hoogenboom, Bart W; Richter, Ralf P

2016-01-01

The permeability barrier of nuclear pore complexes (NPCs) controls bulk nucleocytoplasmic exchange. It consists of nucleoporin domains rich in phenylalanine-glycine motifs (FG domains). As a bottom-up nanoscale model for the permeability barrier, we have used planar films produced with three different end-grafted FG domains, and quantitatively analyzed the binding of two different nuclear transport receptors (NTRs), NTF2 and Importin β, together with the concomitant film thickness changes. NTR binding caused only moderate changes in film thickness; the binding isotherms showed negative cooperativity and could all be mapped onto a single master curve. This universal NTR binding behavior – a key element for the transport selectivity of the NPC – was quantitatively reproduced by a physical model that treats FG domains as regular, flexible polymers, and NTRs as spherical colloids with a homogeneous surface, ignoring the detailed arrangement of interaction sites along FG domains and on the NTR surface. DOI: http://dx.doi.org/10.7554/eLife.14119.001 PMID:27058170